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Dispatchable Capability of Aggregated Electric Vehicle Charging in Distribution Systems 被引量:1
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作者 Shiqian Wang Bo Liu +4 位作者 Yuanpeng Hua Qiuyan Li Binhua Tang Jianshu Zhou Yue Xiang 《Energy Engineering》 EI 2025年第1期129-152,共24页
This paper introduces a method for modeling the entire aggregated electric vehicle(EV)charging process and analyzing its dispatchable capabilities.The methodology involves developing a model for aggregated EV charging... This paper introduces a method for modeling the entire aggregated electric vehicle(EV)charging process and analyzing its dispatchable capabilities.The methodology involves developing a model for aggregated EV charging at the charging station level,estimating its physical dispatchable capability,determining its economic dispatchable capability under economic incentives,modeling its participation in the grid,and investigating the effects of different scenarios and EV penetration on the aggregated load dispatch and dispatchable capability.The results indicate that using economic dispatchable capability reduces charging prices by 9.7%compared to physical dispatchable capability and 9.3%compared to disorderly charging.Additionally,the peak-to-valley difference is reduced by 64.6%when applying economic dispatchable capability with 20%EV penetration and residential base load,compared to disorderly charging. 展开更多
关键词 Aggregated charging dispatchable capability peak shaving and valley filling the economics of charging demand response
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An asymmetrically variable wingtip anhedral angles morphing aircraft based on incremental sliding mode control:Improving lateral maneuver capability 被引量:2
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作者 Xiaodong LIU Yong XU Jianqiao LUO 《Chinese Journal of Aeronautics》 2025年第1期455-470,共16页
This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic mo... This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual inputs.Secondly,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown disturbances.The whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function method.Furthermore,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and rudder.Actuator dynamic models are incorporated to ensure physical realizability of designed allocation law.Finally,comparative experimental results validate the effectiveness of the designed control system and control allocation law.The NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),respectively.The design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering. 展开更多
关键词 Morphing aircraft Lateral maneuver capability Incremental sliding mode control Multi-Lyapunov function method Control theory Control allocation law
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Observation on the Intervention Effect of Emergency Rescue Capability Among College Students
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作者 Beiyan Zhang 《Journal of Clinical and Nursing Research》 2025年第4期265-272,共8页
Objective:To explore the application effect of emergency rescue capability intervention among students in a university in Beijing.Methods:A total of 900 students from a university in Beijing in 2023 were selected as t... Objective:To explore the application effect of emergency rescue capability intervention among students in a university in Beijing.Methods:A total of 900 students from a university in Beijing in 2023 were selected as the research objects.Emergency rescue capability training was conducted from March 2023 to June 2023,once a month.The students’mastery of emergency rescue before and after the intervention was analyzed.Survey questionnaires were distributed to all college students to understand their channels and willingness to acquire emergency rescue knowledge.Results:A total of 886 valid questionnaires were collected in this study.The highest proportion of knowledge about China’s general emergency telephone number and how to dial the emergency rescue hotline was 100.00%.Among the strategies for dealing with cardiac arrest in CPR,the highest proportion was 336.34%.Among the four major first aid techniques of hemostasis,bandaging,fixation,transportation,the highest proportion of knowledge about the use of rubber band signs was 31.71%.Among the first aid techniques for heatstroke,poisoning,fire,and sharp instrument injuries,the principle of emergency treatment for severe gas poisoning had the highest proportion of 41.42%,showing significant differences.College students mainly acquire knowledge of emergency rescue capability through TV programs,health education lectures,and the internet.Around 61.40%of college students hope to learn more about prevention and control knowledge.Conclusion:After the intervention of emergency rescue capability,the emergency rescue capability of college students in this university has been significantly improved,showing a strong training effect,which is worthy of promotion. 展开更多
关键词 UNIVErSITY Emergency rescue capability Emergency rescue capability intervention
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Dual Cross-linked Eucommia Ulmoides Gum with Reprocessibility,Shape Memory Capability and Broadband Sound Absorption at Low Frequency
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作者 Qing-Gang Ni Rui Mi +4 位作者 Biao Ou-Yang Jian-Hua Wu Peng Kong You-Ji Li Xiao-Chun Peng 《Chinese Journal of Polymer Science》 2025年第10期1875-1884,共10页
An inverse vulcanized polymer,SZIM combining Zn2+-imidazole coordination bonds and polysulfide bonds was synthesized and incorporated into bio-based Eucommia ulmoides gum (EUG) to generate EUG-SZIM-xs.The residual cry... An inverse vulcanized polymer,SZIM combining Zn2+-imidazole coordination bonds and polysulfide bonds was synthesized and incorporated into bio-based Eucommia ulmoides gum (EUG) to generate EUG-SZIM-xs.The residual crystallinity of the EUG matrix synergistically interacted with the dual cross-linking networks to establish reversible deformation domains,providing EUG-SZIM-xs with quick shape memory capability at moderate temperatures.The damping properties were also investigated,and EUG-SZIM-xs displayed high tanδ values (>0.3) when the SZIM dosage was higher than 5.5 phr,which showed a positive correlation with SZIM concentration.Such good damping performance endowed the EUG-SZIM-xs with broadband low-frequency sound absorption.In addition,the dual cross-linking networks endowed the materials with reprocessability under different catalytic systems,and the 1,8-diazobicyclic[5.4.0]undeca-7-ene (DBU)-catalyzed samples exhibited better mechanical properties than EUG-SZIM-xs. 展开更多
关键词 Eucommia ulmoides gum Inverse vulcanization Shape memory capability reprocessibility Sound absorption
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Alternative Lens to Understand the Relationships Between Neighborhood Environment and Well-being with Capability Approach and Explainable Artificial Intelligence
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作者 JIAO Linshen ZHANG Min +4 位作者 ZHEN Feng QIN Xiao CHEN Peipei ZHANG Shanqi HU Yuchen 《Chinese Geographical Science》 2025年第3期472-491,共20页
The relationship between the neighborhood environment and well-being is attracting increasingly attention from researchers and policymakers,as the goal of development has shift from economy to well-being.However,exist... The relationship between the neighborhood environment and well-being is attracting increasingly attention from researchers and policymakers,as the goal of development has shift from economy to well-being.However,existing literature predominantly adopts the utilitarian approach,understanding well-being as people’s feelings about their lives and viewing the neighborhood environment as resources that benefit well-being.The Capability Approach,a novel approach that conceptualize well-being as the freedoms to do or to be and regard environment as conversion factors that influence well-being,can offer new lens by incorporating human development in-to these topics.This paper proposes an alternative theoretical framework:well-being is conceptualized and measured by capability;neighborhood environment affects well-being by providing spatial services,functioning as environmental conversion factors,and serving as social conversion factors.We conducted a case study of Changshu City located in eastern China,utilizing multiple resource data,applying explainable artificial intelligence(XAI),namely eXtreme Gradient Boosting(XGBoost)and SHapley Additive exPlana-tions(SHAP).Our findings highlight the significance of viewing the neighborhood environment as a set of conversion factors,as it provides more explanatory power than providing spatial services.Compared to conventional research based on linear relationship as-sumption,our results demonstrate that the effects of neighborhood environment on well-being are non-linear,characterized by threshold effects and interaction effects.These insights are crucial for informing urban planning and public policy.This research enriches our un-derstanding of well-being,neighborhood environment,and their relationship as well as provides empirical evidence for the core concept of conversion factors in the capability approach. 展开更多
关键词 WELL-BEING neighborhood environment capability approach non-linear relationship explainable artificial intelligence(XAI)
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Research on evaluation of basic railway safety management capability based on combination weighting–TOPSIS
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作者 Yankun Qi Xiaoyu Li +2 位作者 Jinghui Liu Hanqiu Li Chen Yang 《Railway Sciences》 2025年第1期108-122,共15页
Purpose–To systematically characterize and objectively evaluate basic railway safety management capability,creating a closed-loop management approach which allows continuous improvement and optimization.Design/method... Purpose–To systematically characterize and objectively evaluate basic railway safety management capability,creating a closed-loop management approach which allows continuous improvement and optimization.Design/methodology/approach–A basic railway safety management capability evaluation index system based on a comprehensive analysis of national safety management standards,railway safety rules and regulations and existing safety data from railway transport enterprises is presented.The system comprises a guideline layer including safety committee formation,work safety responsibility,safety management organization and safety rules and regulations as its components,along with an index layer consisting of 12 quantifiable indexes.Game theory combination weighting is utilized to integrate subjective and objective weight values derived using AHP and CRITIC methods and further combined using the TOPSIS method in order to construct a comprehensive basic railway safety management capability evaluation model.Findings–The case study presented demonstrates that this evaluation index system and comprehensive evaluation model are capable of effectively characterizing and evaluating basic railway safety management capability and providing directional guidance for its sustained improvement.Originality/value–Construction of an evaluation index system that is quantifiable,generalizable and accessible,accurately reflects the main aspects of railway transportation enterprises’basic safety management capability and provides interoperability across various railway transportation enterprises.The application of the game theoretic combination weighting method to derive composite weights which combine experts’subjective evaluations with the objectivity of data. 展开更多
关键词 railway transportation enterprises Basic safety management capability Evaluation index system Combination weighting
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Topological Structure Design and Obstacle-climbing Capability Analysis of a Lizard-inspired Torso-leg-foot Biomimetic Robot
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作者 Yuting Du Yan-an Yao +1 位作者 Qiang Ruan Wenbo Mi 《Journal of Bionic Engineering》 2025年第1期65-82,共18页
Lizards are one of the most primitive reptiles in existence,with special limb structures that enable them to move quickly across diverse and complex terrains such as rock piles,shallow shoals,and deserts.A thorough ex... Lizards are one of the most primitive reptiles in existence,with special limb structures that enable them to move quickly across diverse and complex terrains such as rock piles,shallow shoals,and deserts.A thorough exploration was conducted on the biomimetic mechanism and ground-touching mechanism of lizard limbs from both micro and macro perspectives.Inspired by the intricate torso and limb configurations of lizards,a novel Torso-leg-foot biomimetic robot has been conceptualized based on the design of the Big-Foot robot.This robot integrates a Torso-leg-foot system,featuring a parallel torso biomimetic structure with a 2-SPR/UPU/UPR(P)configuration.It utilizes the theory of finite screws to articulate the instantaneous movements of the parallel torso,and the inverse kinematics of this mechanism have been calculated.The reachable workspace of the 2-SPR/UPU/UPR parallel mechanism using FIS theory,which is closely related to the climbing height of the robot.A comprehensive dimension synthesis was conducted on the leg-foot system,and the adoption of the three-pair rod drive method was determined by investigating its Variable Rotating Velocity Characteristics(VRVC).Simulation tests have shown that with an integrated torso,the robot can climb vertical obstacles up to 600 mm in height.The experimental tests of climbing steps and slopes using physical prototypes have confirmed the robot's obstacle-crossing capability.The potential applications of this Torso-leg-foot biomimetic robot is to carry heavy objects across obstacles to perform tasks such as planetary exploration and disaster relief. 展开更多
关键词 Torso-leg-foot Lizard biomimetics Topological structure Variable rotating Velocity Characteristics(VrVC) Obstacle-climbing capability
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Stereoisomeric engineering mediated zinc metal electrodeposition:Critical balance of solvation and adsorption capability
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作者 Wen Liu Qiwen Zhao +7 位作者 Ruheng Jiang Xuyan Ni Tiancheng You Canglong Li Yanzi Deng Bingang Xu Yuejiao Chen Libao Chen 《Advanced Powder Materials》 2025年第2期76-85,共10页
The exceptional electrochemical performance of zinc anodes is frequently impeded by inadequate deposition kinetics and interfacial chemistry.Herein,we introduce the stereoisomerism to inform the balanced selection of ... The exceptional electrochemical performance of zinc anodes is frequently impeded by inadequate deposition kinetics and interfacial chemistry.Herein,we introduce the stereoisomerism to inform the balanced selection of electrolyte additives,taking into account their solvation and adsorption properties,to achieve the optimal deposition behaviors and electrochemical performance.The three-point coplanar adsorption configuration,in comparison to two-point adsorption,effectively mitigates the interference of water molecules and establishes a coplanar templating effect.This approach fosters a uniform distribution of charges,encourages the preferential orientation growth of(002)planes for uniform zinc deposition.Moreover,an appropriate level of solvation ability can modulate the solvation structure without substantially increasing the de-solvation energy barrier,thereby facilitating faster deposition kinetics than what is observed in cases of strong solvation.As a result,Zn//Zn cell can achieve an excellent performance of more than 3470 h at 2 mA cm^(-2)and 1 mAh cm^(-2),and Zn//AC full cell can work for 50000 cycles at 3 A g^(-1).Additionally,under practical conditions(N/P=4.37),the assembled Zn//I2 full cell demonstrates stable lifespan for 710 cycles at 1 A g^(-1).This work showcases the interplay between adsorption configuration of stereoisomeric additives on the cycling. 展开更多
关键词 Stereoisomeric additives Structure-activity relationship Coplanar templating effect Solvation and adsorption capability Optimized zinc deposition behavior
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Plasmonic dual-parameter biosensor with self-referencing capability based on one-dimensional metal gratings
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作者 LIU Jun LUO Jianhua 《Optoelectronics Letters》 2025年第8期449-454,共6页
There is limited amount of research on surface plasmon resonance(SPR)sensors with self-referencing capabilities which are based on dielectric gratings.In the short-wavelength range,a metal grating sensor is capable of... There is limited amount of research on surface plasmon resonance(SPR)sensors with self-referencing capabilities which are based on dielectric gratings.In the short-wavelength range,a metal grating sensor is capable of simultaneously measuring liquid refractive index under proposed temperature.A fabricated gold grating is placed on one side of a thin gold film for refractive index measurement,while the other with polydimethylsiloxane(PDMS)is deposited on the other side for temperature measurement.We use finite element analysis to research its sensing characteristics.Due to the high refractive index sensitivity of SPR sensors and thermo-optic coefficient of PDMS,we discovered the maximum spectral sensitivity of the sensor is 564 nm/RIU and-50 pm/℃when the liquid refractive index ranges from 1.30 to 1.40 with temperature ranging from 0℃ to 100℃.Numerical results indicate that there may not be mutual interference between two channels for measuring refractive index and temperature,which reduces the complexity of sensor measurements. 展开更多
关键词 thin gold film fabricated gold grating plasmonic biosensor metal grating sensor liquid refractive index self referencing capability refractive index dielectric gratingsin
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供应链金融对中小企业R&D投资效率的影响:基于融资约束视角 被引量:6
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作者 胡海青 原敏倩 薛萌 《科技进步与对策》 北大核心 2025年第1期102-112,共11页
创新是中小企业保持竞争力、适应市场变化和实现可持续发展的关键。基于2016-2022年创业板中小企业相关数据,运用三阶段DEA分析、面板Tobit模型回归、二元Logistic回归等方法,探究供应链金融对中小企业R&D投资效率的影响。结果表明... 创新是中小企业保持竞争力、适应市场变化和实现可持续发展的关键。基于2016-2022年创业板中小企业相关数据,运用三阶段DEA分析、面板Tobit模型回归、二元Logistic回归等方法,探究供应链金融对中小企业R&D投资效率的影响。结果表明,供应链金融能够显著提高中小企业R&D投资效率,融资约束在二者间发挥遮掩效应。进一步分析发现,上述效应对供应链集中度较高的企业更为显著。结论可为发挥供应链金融筹资优势,促进供应链生态系统资源互补、信息共享的协同创新网络形成,进而支持中小企业创新活动提供理论支持。 展开更多
关键词 供应链金融 r&d投资效率 三阶段dEA 面板Tobit模型 遮掩效应
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经济政策不确定性、风险感知与企业R&D投资阶段选择
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作者 成力为 吴薇 《管理工程学报》 北大核心 2025年第6期1-15,共15页
在经济衰退背景下,企业研发(R&D)投资阶段前移,加大基础研究与应用研究投入是高质量发展的必然选择。本文将外部风险感知到企业内部风险感知的传导过程纳入经济政策不确定性下的企业研发投资决策模型,从资源供给效应和机会成本效应... 在经济衰退背景下,企业研发(R&D)投资阶段前移,加大基础研究与应用研究投入是高质量发展的必然选择。本文将外部风险感知到企业内部风险感知的传导过程纳入经济政策不确定性下的企业研发投资决策模型,从资源供给效应和机会成本效应揭示影响企业研究阶段与开发阶段投资选择的机制。接着,利用2011—2020年中国上市制造业企业数据进行实证检验发现:(1)在机会成本效应主导下,经济政策不确定性对企业研究阶段投资存在显著激励作用;当资源供给效应占主导时,经济政策不确定性对开发阶段投资具有显著的抑制作用;(2)机制分析发现,经济政策不确定性上升会增强银行短期信贷偏好,进而抑制企业研究阶段投资。这进一步强化了企业内部风险感知,企业会通过“短债长用”等措施放大机会成本效应,从而有效缓解了短期信贷对研究阶段投资的负面影响。这种影响在高成熟度、低融资约束和低短期借款依赖度的企业中更为明显。此外,在资源供给效应主导下,经济政策不确定性可以通过降低股票流动性来抑制企业开发阶段投资。本文强调经济政策不确定性首先被金融机构和资本市场感知,接着通过外部融资约束传导至企业内部,进而强化企业的风险感知,使企业能够利用规避风险工具调节不同阶段的研发投资。 展开更多
关键词 经济政策不确定性 r&d投资阶段 风险感知 机会成本效应 资源供给效应
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基于因子分析的政府R&D投入绩效评价
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作者 赵志泉 林艳艳 李志敏 《科技和产业》 2025年第12期308-314,共7页
创新驱动为经济社会发展提供新动能,是引领未来经济转型的核心途径。政府R&D投入反映国家意志,有必要对其产出效率进行评价。利用2018—2022年31个省份(因数据缺失,未包含港澳台地区)的面板数据,从投入产出两个方面选取13个具体指... 创新驱动为经济社会发展提供新动能,是引领未来经济转型的核心途径。政府R&D投入反映国家意志,有必要对其产出效率进行评价。利用2018—2022年31个省份(因数据缺失,未包含港澳台地区)的面板数据,从投入产出两个方面选取13个具体指标构建政府R&D投入绩效评价指标体系,采用因子分析法对政府R&D投入绩效进行研究;结合模型的构建以及结果分析,提出通过推进R&D经费投入方式多元化、优化政府R&D经费投入执行结构、提高R&D人员投入来提高政府R&D投入绩效。 展开更多
关键词 政府r&d投入 因子分析 绩效评价
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基于Hyperband-贝叶斯优化-LSTM网络的高旋尾控修正弹修正能力研究
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作者 周杰 王良明 +2 位作者 傅健 王彦钦 郭首邑 《兵工学报》 北大核心 2025年第7期248-258,共11页
为快速准确地解算出高旋尾控修正弹的修正指令,针对其能力预测问题,提出一种基于Hyperband算法-贝叶斯优化-长短期记忆网络(Hyperband algorithm-Bayesian optimization-Long Short-Term Memory network,HBBO-LSTM)的修正能力预测模型... 为快速准确地解算出高旋尾控修正弹的修正指令,针对其能力预测问题,提出一种基于Hyperband算法-贝叶斯优化-长短期记忆网络(Hyperband algorithm-Bayesian optimization-Long Short-Term Memory network,HBBO-LSTM)的修正能力预测模型。建立高旋尾控修正弹的7自由度弹道模型,并使用龙格-库塔法进行数值仿真,生成大量样本数据;通过对数据集的分析,提出一种基于拉马努金近似公式的预处理方式,对原始数据集进行预处理,获得空间分布均匀的样本数据。构建HBBO-LSTM网络预测模型,通过训练得到模型的最佳结构参数。提出一种融合带重启机制的余弦退火衰减和指数衰减的学习率下降策略,保证训练过程的快速性和稳定性。将所述模型与长短期记忆网络模型、门控循环单元网络模型和反向传播网络模型在同一测试集下进行仿真实验,并与4自由度修正质点弹道方程数值积分法进行实验对比。研究结果表明,HBBO-LSTM网络模型的综合均方误差为0.17 m^(2),综合平均绝对误差为0.33 m,预测精度优于其他模型;且解算时间和预测精度均优于数值积分法,具有较高的可行性和参考价值。 展开更多
关键词 修正能力 弹道修正弹 尾控弹 长短期记忆网络 Hyperband算法 贝叶斯优化
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云南省研发(R&D)人员发展现状分析 被引量:1
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作者 王金凤 李艳芬 +1 位作者 甘敏 杨映明 《云南科技管理》 2025年第3期22-26,共5页
创新发展关键在人才,而研发(R&D)人员是推动科技创新、实现技术革新与突破、促进经济增长和社会进步的核心力量。文章对云南省2019-2023年研发人员规模、结构、投入强度与全国平均水平进行比较分析,通过数据包络(DEA)分析模型测算... 创新发展关键在人才,而研发(R&D)人员是推动科技创新、实现技术革新与突破、促进经济增长和社会进步的核心力量。文章对云南省2019-2023年研发人员规模、结构、投入强度与全国平均水平进行比较分析,通过数据包络(DEA)分析模型测算云南省16个州市研发人员的投入产出效率,从政策、教育、企业、环境等维度提出推进云南省研发人员队伍建设的措施建议,为我省科技创新和经济社会发展提供有力的人才支撑。 展开更多
关键词 云南省 r&d人员 比较分析 投入产出效率
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绿色金融、R&D投入与碳排放的内在关联性研究——基于省际面板数据的实证检验 被引量:1
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作者 刘伟 纪明 +1 位作者 韩进 王竞一 《工业技术经济》 北大核心 2025年第3期45-55,共11页
“碳达峰”和“碳中和”目标下,如何推动中国碳减排与经济绿色低碳转型,已经成为中国高质量发展的重要议题。本文基于2010~2022年我国30个省(区、市)的面板数据,探析了绿色金融和科技研发对碳排放的影响,实证证明了绿色金融与R&D投... “碳达峰”和“碳中和”目标下,如何推动中国碳减排与经济绿色低碳转型,已经成为中国高质量发展的重要议题。本文基于2010~2022年我国30个省(区、市)的面板数据,探析了绿色金融和科技研发对碳排放的影响,实证证明了绿色金融与R&D投入均对碳排放起到显著的抑制作用,而且R&D投入在绿色金融与碳排放之间的起到显著的负向调节作用,它既是绿色金融政策落地的关键驱动力,也是减少碳排放的重要技术手段。因此,我国应当加强绿色金融政策支持、发挥R&D投入和技术创新在实现碳减排中的关键驱动作用,同时推动绿色金融与科技研发协同发展。 展开更多
关键词 绿色金融 科技创新 r&d投入 碳排放 熵权法 单位根检验 区域异质性 科技研发
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城市群R&D人才集聚对企业创新的影响
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作者 靳海攀 胡振华 +1 位作者 魏敏 朱名勋 《系统工程》 北大核心 2025年第3期140-152,共13页
人才集聚对区域创新的积极作用已得到广泛证实,但其对微观层面企业创新的影响机制仍需进一步探讨。本研究从城市群的视角出发,实证分析了R&D人才集聚对企业创新的影响及其内在作用路径。研究结果表明,R&D人才集聚显著提升了城... 人才集聚对区域创新的积极作用已得到广泛证实,但其对微观层面企业创新的影响机制仍需进一步探讨。本研究从城市群的视角出发,实证分析了R&D人才集聚对企业创新的影响及其内在作用路径。研究结果表明,R&D人才集聚显著提升了城市群企业的创新能力,且这一效应在市场化程度较高的大型城市区域以及大型国有企业中更为突出。进一步的机制分析揭示,R&D人才集聚通过推动市场一体化进程、促进知识溢出与共享以及深化产业分工协作,为企业创新提供了重要支撑。本研究为优化城市群人才政策、提升企业创新效能、推动区域协调发展以及实现城市间创新协同提供了理论依据和实践参考。 展开更多
关键词 r&d人才集聚 企业创新 影响机制 城市群
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Streamlined photonic reservoir computer with augmented memory capabilities 被引量:4
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作者 Changdi Zhou Yu Huang +5 位作者 Yigong Yang Deyu Cai Pei Zhou Kuenyao Lau Nianqiang Li Xiaofeng Li 《Opto-Electronic Advances》 2025年第1期45-57,共13页
Photonic platforms are gradually emerging as a promising option to encounter the ever-growing demand for artificial intelligence,among which photonic time-delay reservoir computing(TDRC)is widely anticipated.While suc... Photonic platforms are gradually emerging as a promising option to encounter the ever-growing demand for artificial intelligence,among which photonic time-delay reservoir computing(TDRC)is widely anticipated.While such a computing paradigm can only employ a single photonic device as the nonlinear node for data processing,the performance highly relies on the fading memory provided by the delay feedback loop(FL),which sets a restriction on the extensibility of physical implementation,especially for highly integrated chips.Here,we present a simplified photonic scheme for more flexible parameter configurations leveraging the designed quasi-convolution coding(QC),which completely gets rid of the dependence on FL.Unlike delay-based TDRC,encoded data in QC-based RC(QRC)enables temporal feature extraction,facilitating augmented memory capabilities.Thus,our proposed QRC is enabled to deal with time-related tasks or sequential data without the implementation of FL.Furthermore,we can implement this hardware with a low-power,easily integrable vertical-cavity surface-emitting laser for high-performance parallel processing.We illustrate the concept validation through simulation and experimental comparison of QRC and TDRC,wherein the simpler-structured QRC outperforms across various benchmark tasks.Our results may underscore an auspicious solution for the hardware implementation of deep neural networks. 展开更多
关键词 photonic reservoir computing machine learning vertical-cavity surface-emitting laser quasi-convolution coding augmented memory capabilities
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我国R&D投入对GDP三大产业的影响分析
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作者 扈杨 王桂华 《应用数学进展》 2025年第4期775-782,共8页
为进一步提升中国科技创新竞争力,提高我国R&D投入水平,提升R&D投入使用效率,本文采用相关性检验、逐步回归模型等研究方法分别对物质资本存量、R&D经费内部支出、年末就业人数、R&D人员全时当量和R&D活动组成中的... 为进一步提升中国科技创新竞争力,提高我国R&D投入水平,提升R&D投入使用效率,本文采用相关性检验、逐步回归模型等研究方法分别对物质资本存量、R&D经费内部支出、年末就业人数、R&D人员全时当量和R&D活动组成中的基础研究、应用研究、试验发展与GDP经济指标进行关联度及相互影响分析。每个自变量与GDP、R&D活动中的每个组成部分均与三大产业具有较强关联性,通过测算得出,与基础研究和应用研究相比,试验发展对于三大产业的影响力最为显著。中国高度重视R&D试验发展投入,本论文研究的R&D活动与三大产业关系之间的影响关系结论,能够为R&D投入促进经济社会发展提供有效的研究路径和方向,与此同时也能为政府决策咨询提供建议。 展开更多
关键词 r&d投入 r&d活动 GdP 三大产业
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创新驱动下R&D投入对中国与丝绸之路经济带沿线国家棉产品贸易的影响研究
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作者 王乾润 布娲鹣·阿布拉 +1 位作者 陈俊科 李敬 《工程管理科技前沿》 北大核心 2025年第3期90-96,共7页
伴随创新驱动发展战略实施及“一带一路”深耕细作,强化R&D经费配置,催生双边棉产品贸易发展新动能意义重大。本文采用中国与丝绸之路经济带沿线国家面板数据,运用空间计量模型进行实证分析,结果发现:(1)资源环境、经济发展环境、... 伴随创新驱动发展战略实施及“一带一路”深耕细作,强化R&D经费配置,催生双边棉产品贸易发展新动能意义重大。本文采用中国与丝绸之路经济带沿线国家面板数据,运用空间计量模型进行实证分析,结果发现:(1)资源环境、经济发展环境、科教与创新环境、区域经济合作、空间距离5大项指标共同作用,从不同程度对双边棉产品贸易产生影响;(2)经济发展水平、人口规模、R&D投入、区域贸易协定、跨境人民币结算极大地促进了双边棉产品贸易增长;(3)R&D投入对双边棉产品贸易增长的拉动作用最为显著,R&D投入强度每增加1%,中国与丝绸之路经济带沿线国家棉产品贸易将显著提高2.520%。本文研究对于提升中国与丝绸之路经济带沿线国家棉产品贸易具有一定的参考价值。 展开更多
关键词 创新驱动 r&d 丝绸之路经济带 棉产品国际贸易
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Graphene architecture interpenetrated with mesoporous carbon nanosheets promotes fast and stable potassium storage 被引量:1
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作者 Wenjing Xiong Yulin Xu +5 位作者 Fangzhou Zhao Baokai Xia Hongqiang Wang Wei Liu Sheng Chen Yongzhi Zhang 《Chinese Chemical Letters》 2025年第4期501-506,共6页
Carbon materials are considered as prospective anode candidates for potassium ion batteries(PIBs).However,the low-rate capability is hampered by slow K+diffusion kinetics and obstructed electron transport of carbon-ba... Carbon materials are considered as prospective anode candidates for potassium ion batteries(PIBs).However,the low-rate capability is hampered by slow K+diffusion kinetics and obstructed electron transport of carbon-based anodes.In this work,calcium D-gluconate derived mesoporous carbon nanosheets(CGC)were interpenetrated into the architecture of reduced graphene oxides(RGO)to form the composites of two-dimensional(2D)/2D graphene/mesoporous carbon nanosheets(RGO@CGC).CGC as a rigid skeleton can prevent the graphene layers from restacking and maintain the structural stability of the 2D/2D carbon composites of RGO@CGC.The mesopores in CGC can shorten the path of ion diffusion and facilitate the penetration of electrolytes.RGO possesses the high surface-to-volume ratio and superior electron transport capability in the honeycomb-like 2D network consisting of sp^(2)-hybridized carbon atoms.Especially,theπ-πstacking interaction between CGC and RGO enhances stable composite structure formation,expedites interlayer-electron transfer,and establishes three-dimensional(3D)ion transportation pathways.Owing to these unique structure,RGO@CGC exhibits fast and stable potassium storage capability.Furthermore,the effects of binders and electrolytes on the electrochemical performance of RGO@CGC were investigated.Finally,Prussian blue was synthesized as a positive electrode to explore the possibility of RGO@CGC as a full battery application. 展开更多
关键词 Potassium storage GrAPHENE Mesoporous carbon nanosheets Composite High-rate capability
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