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Multi-effect distillation system for seawater desalination driven by tidal energy and low grade energy 被引量:2
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作者 刘业凤 胡海涛 马福一 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期343-345,共3页
A multi-effect distillation technology for seawater desalination driven by tidal energy and low grade energy is presented.In the system,tidal energy is utilized to supply power instead of coventional electric pumps du... A multi-effect distillation technology for seawater desalination driven by tidal energy and low grade energy is presented.In the system,tidal energy is utilized to supply power instead of coventional electric pumps during the operation,resulting in the decrease of dependence on steady electric power supply and a reduction in the running costs.According to the technological principle,a testing unit is designed and built.The effects of the feed seawater temperature and the heat source temperature on the unit performance are tested and analyzed.The experimental results show that the fresh water output is 27 kg/h when the heating water temperature is 65 ℃ and the absolute pressure is 25 kPa.The experimental and theoretical analysis results indicate that the appropriate heating water temperature is a key factor in ensuring the steady operation of the system. 展开更多
关键词 multi-effect distillation for seawater desalination tidal energy low grade energy VACUUM
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Chemical dehydration coupling multi-effect evaporation to treat waste sulfuric acid in titanium dioxide production process 被引量:12
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作者 Hongyin Pang Ruifang Lu +3 位作者 Tao Zhang Li Lü Yanxiao Chen Shengwei Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第4期1162-1170,共9页
In order to concentrate the diluted sulfuric acid from the titanium dioxide(TiO2)production of sulphate process,a new concentration process was proposed by coupling chemical dehydration and multi-effect evaporation.Th... In order to concentrate the diluted sulfuric acid from the titanium dioxide(TiO2)production of sulphate process,a new concentration process was proposed by coupling chemical dehydration and multi-effect evaporation.The ferrous sulfate monohydrate(FeSO4·H2O),as the dehydrant,was added to the diluted sulfuric acid to form ferrous sulfate heptahydrate(FeSO4·7H2O)according to the H2SO4-FeSO4-H2O phase diagrams,which partially removes the water.This process was named as Chemical Dehydration Process.The residual water was further removed by two-effect evaporation and finally 70 wt%sulfuric acid was obtained.The FeSO4·H2O can be regenerated through drying and dehydration of FeSO4·7H2O.The results show that FeSO4·H2O is the most suitable dehydrant,the optimal reaction time of chemical dehydration process is 30 min,and low temperature is favorable for the dehydration reaction.45.17%of the entire removed water can be removed by chemical dehydration from the diluted sulfuric acid.This chemical dehydration process is also energy efficient with 24.76%saving compared with the direct evaporation process.Furthermore,51.21%of the FeSO4 dissolved originally in the diluted sulfuric acid are precipitated out during the chemical dehydration,which greatly reduces the solid precipitation and effectively alleviates the scaling in the subsequent multi-effect evaporation process. 展开更多
关键词 Chemical dehydration multi-effect evaporation Sulfuric acid TITANIUM
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Selecting Suitable Heat Source in Refinery for Multi-effect Distillation Based on Grey System Theory 被引量:1
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作者 Xue Jianliang Zhao Dongfeng +3 位作者 Li Shi Liu Wei Shen Chanchan Chen Lu 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第1期66-72,共7页
For dealing with high-salinity wastewater in the refinery, the high cost of driving heat source is the disadvantage of multi-effect distillation (MED) so it is of great importance to evaluate the performance of low-te... For dealing with high-salinity wastewater in the refinery, the high cost of driving heat source is the disadvantage of multi-effect distillation (MED) so it is of great importance to evaluate the performance of low-temperature heat source for conducting MED and select the optimal temperature for it. Both the MED and the low-temperature heat sources studied in this paper were from a typical refinery located in northwestern China. Besides, a new methodology to evaluate heat sources as the optimal candidate was proposed for MED based on the grey system theory. Five process units, which included 18 fluids of the refinery, were named as the evaluation projects. Three factors, which included safety effects, total costs and characteristics of low-temperature heat sources were determined as the evaluation indexes, the values of which were established through the analyses. The results obtained through the grey correlation analyses have revealed that the grey correlation degrees of these units were 0.661(AVDU), 0.732 (#1 FCCU), 0.618 (#2 FCCU), 0.535 (#1 DCU), and 0.572 (#2 DCU), respectively. Thus, the optimal heat source was provided from #1 FCCU. Through further analyses of the fluids from #1 FCCU, the grey correlation degrees of the fluids were 0.597 (oil and gas at top of tower), 0.714 (recycle oil and gas), and 0.512 (diesel), respectively. Thus, the optimal heat source was the oil and gas recycle stream. 展开更多
关键词 multi-effect distillation grey system theory heat recovery high-salinity wastewater REFINERY
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Study on Multi-effect Time Parameters of Ergonomic Validity Index in Low-carbon Residential Kitchen
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作者 Jun Ji Hong Jin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第5期52-58,共7页
In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts... In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts of human factors on quantitative study,it proposes a method of building a parameter of ergonomic validity—multi-effect time by using cardiotachometer to record heart rate change,being used to evaluate the functional low-carbon ergonomic validity targeting at the ontological characteristics of kitchen. This method is used to determine the physical consumption intensity( multi-effect) through heart rate incremental relation based on the principles of physiology and ergonomics,and to confirm the ergonomic validity of environmental factors by the time to complete standard work as well as multi-effect quantitative analysis. The test results show that,under the kitchen operating conditions,the multi-effect( ME) can properly reflect the real-time status of the operator and is easily operated; the parameters obtained are not significantly related to the physiological status of the operator,and multi-effect time( MT) is sensitive to the physical consumption brought about to the operator due to kitchen environmental factors; thus,it can be taken as an objective index,which is simple and easy to operate in residential kitchen functional low-carbon evaluation. 展开更多
关键词 functional low-carbon human factors ergonomic validity index basal heart rate increment ratio multi-effect time of kitchen work
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Multi-effects and Mechanism of Broad Beau M_1 Root-tip Cells Implanted by Low Energy N^+ Beam
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作者 徐谷峰 顾月华 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第3期835-840,共6页
Broad beans were divided into six groups and implanted with N+ beam of 30 KeV, 8 × 1016/cm2 per time for various radiating times respectively. Besides the statistics of its vigor of germination, the M1 root-tip c... Broad beans were divided into six groups and implanted with N+ beam of 30 KeV, 8 × 1016/cm2 per time for various radiating times respectively. Besides the statistics of its vigor of germination, the M1 root-tip cells of these broad beans were systematically analyzed on their changes in mitotic percentage, morphology and behavior of chromosomes, along with the structure o f cytoskeletons, including microtubule and intermediate filament. Based on all results of these studies, our opinions have been expressed in the report on the mechanism of low-energy N+ beams effecting on higher dicotyledons such as broad beau. 展开更多
关键词 BEAM multi-effects and Mechanism of Broad Beau M1 Root-tip Cells Implanted by Low Energy N
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Simulation of Countercurrent Multi-Effect Drying System
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作者 Hong Li Lianying Wu +1 位作者 Xianli Wu Yangdong Hu 《Advances in Materials Physics and Chemistry》 2012年第4期206-211,共6页
The paper bulids a countercurrent multi-effect drying process model which can be expressed as a linear programming(LP) problem with the minimum total energy consumption as target function. Based on the model it can be... The paper bulids a countercurrent multi-effect drying process model which can be expressed as a linear programming(LP) problem with the minimum total energy consumption as target function. Based on the model it can be conventient to solve the heat load , degree of drying and other drying parameters of each effect. And it realizes the mathematical simulation an analysis of multi-effect drying process. Such process not only reuses the secondary steam but also utilizes the high energy grade. Drying silica sand using 1-effect drying to 5-effect drying is presented as an example. The energy consumption and energy saving rate are compared by using co-current multi-effect drying and countercurrent multi-effect drying. As a summary, the countercurrent multi-effect drying is better than co-current drying. Considered the equipment investment and energy conservation, the study also concluded that the countercurrent 4-effect drying is the optimum selection, and it can save 57.6% energy compared to countercurrent 1-effect drying. 展开更多
关键词 Countercurrent DRYING multi-effect DRYING SECONDARY STEAM LP
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营商环境驱动城市绿色创新效率提升的多元路径分析
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作者 肖仁桥 高倩 +1 位作者 王宗军 钱丽 《科技进步与对策》 北大核心 2026年第3期44-55,共12页
基于复杂系统观和绿色创新链理论,利用多时段fsQCA和三阶段DEA模型,选取长三角、珠三角及京津冀地区的49个城市作为研究样本,从动态视角探究营商环境驱动城市绿色创新效率提升的作用路径及演变规律。结果表明:①任何单一的营商环境要素... 基于复杂系统观和绿色创新链理论,利用多时段fsQCA和三阶段DEA模型,选取长三角、珠三角及京津冀地区的49个城市作为研究样本,从动态视角探究营商环境驱动城市绿色创新效率提升的作用路径及演变规律。结果表明:①任何单一的营商环境要素均不是引致高绿色创新效率的必要条件;②不同阶段实现高绿色创新效率的组态路径不同,绿色知识创新阶段存在资源协同驱动型和政务市场驱动型2条路径,绿色科技创新阶段存在创新主导支撑型、金融政府协同型、政府市场共促型和创新资源整合型4条路径,绿色产品创新阶段存在金融人力融合型路径;③营商环境要素呈现出主导、缓冲主导和转折轨迹作用特征。在绿色知识创新阶段,政务环境、市场环境、创新环境、人力资源和公共服务发挥主导轨迹作用;在绿色科技创新阶段,公共服务发挥主导轨迹作用,而市场环境和创新环境发挥转折轨迹作用;在绿色产品创新阶段,主导轨迹因素为市场环境和创新环境。 展开更多
关键词 营商环境 绿色创新效率 多时段fsQCA 组态效应
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部分强化效应驱动的大规模多目标优化问题求解算法
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作者 顾清华 王晗睿 +1 位作者 王倩 骆家乐 《计算机工程与应用》 北大核心 2026年第1期172-191,共20页
针对大规模多目标优化问题中决策空间维度高、收敛难及计算资源分配低效等挑战,提出部分强化效应驱动的大规模多目标优化问题求解算法DVA-PRO。该算法通过决策变量二元化重构原目标问题以降维,利用部分强化效应理论设计评估与正强化机制... 针对大规模多目标优化问题中决策空间维度高、收敛难及计算资源分配低效等挑战,提出部分强化效应驱动的大规模多目标优化问题求解算法DVA-PRO。该算法通过决策变量二元化重构原目标问题以降维,利用部分强化效应理论设计评估与正强化机制,动态分配计算资源——优化初期高倍率强化促进收敛,后期扩大强化范围维护多样性。DVA-PRO与6种对比算法在100例大规模多目标优化基准测试问题上进行对比实验,并在4类实际工程应用问题上进行仿真。实验结果表明,DVA-PRO在79例基准测试问题和所有实际工程应用问题上性能指标排名第一。在相同计算资源限制下,DVA-PRO能有效搜索并收敛至帕累托前沿,综合性能优于其他算法,并在不同类型的大规模多目标优化问题上兼具高效性与通用性。 展开更多
关键词 进化算法 大规模优化 多目标优化 部分强化效应 问题重构
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自贸试验区建设对周边地区出口贸易高质量发展的影响研究
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作者 余升国 黄娜 关智化 《南海学刊》 2026年第1期25-36,共12页
中国自贸试验区东部沿海先行先试向全国辐射,在区域经济增长与贸易活力激活中成效显著。基于2008—2022年中国215个地级市面板数据,采用双重差分法,评估自贸试验区设立对周边出口贸易高质量发展的溢出效应及其作用机制。研究发现:自贸... 中国自贸试验区东部沿海先行先试向全国辐射,在区域经济增长与贸易活力激活中成效显著。基于2008—2022年中国215个地级市面板数据,采用双重差分法,评估自贸试验区设立对周边出口贸易高质量发展的溢出效应及其作用机制。研究发现:自贸试验区虽为周边区域搭建了高技术复杂度产品的出口通道,但周边区域优势资源向试验区的持续流入,对周边地区出口贸易高质量发展形成了短暂的虹吸效应。异质性分析表明,在批次层面,第一、二批次自贸试验区负向效应更突出;地理层面,东部沿海自贸试验区负向溢出强度更显著;城市等级层面,高等级城市受政策影响大于低等级城市。机制分析表明,自贸试验区短期内通过要素集聚效应吸附周边区域的产业结构与数字经济资源,进而对周边区域出口贸易高质量发展形成显著冲击。 展开更多
关键词 自贸试验区 出口技术复杂度 溢出效应 虹吸效应 多期DID
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Screening the emission sources of volatile organic compounds (VOCs) in China by multi-effects evaluation 被引量:16
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作者 He NIU Ziwei MO +2 位作者 Min SHAO Sihua LU ShaodongXIE 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2016年第5期25-35,共11页
Volatile organic compounds (VOCs) play important roles in the atmosphere via three main pathways: photochemical ozone formation, secondary organic aerosol production, and direct toxicity to humans. Fewstudies have ... Volatile organic compounds (VOCs) play important roles in the atmosphere via three main pathways: photochemical ozone formation, secondary organic aerosol production, and direct toxicity to humans. Fewstudies have integrated these effect, s to prioritize control measures for VOC.s sources. In this study,we developed a multi-effects evaluation methodology based on updated emission inventories and source profiles, by combining the ozone formation potential (OFP), secondary organic aerosol potential (SOAP), and VOC toxicity data. We derived species-specific emission inventories for 152 sources. The OFPs, SOAPs, and toxicity of each source were estimated, the contribution and sharing of source to each of these adverse effects were calculated. Weightings were given to the three adverse effects by expert scoring, and then the integrated effect was determined. Taking 2012 as the base year,solvent use and industrial process were found to be the most important anthropogenic sources, accounting for 24.2% and 23.1% of the integrated effect, respectively, followed by biomass burning, transportation, and fossil fuel combustion, each had a similar contribution ranging from 16.7% to 18.6%. The top five industrial sources, including plastic products, rubber products, chemical fiberproducts, the chemical industry, and oil refining, accounted for nearly 70.0% of industrial emissions. Beijing, Chongqing, Shanghai, Jiangsu, and Guangdong were the five provinces contributing the largest integrated effects. For the VOC species from emissions showed the largest contributions were styrene, toluene, ethylene, benzene, and m/p-xylene. 展开更多
关键词 Ozone formation Secondary organic aerosol multi-effects evaluation VOC abatement strategy
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刚柔复合桩承载行为的施工与界面效应:研究现状与展望
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作者 英姿 邓康威 +2 位作者 邓永锋 钱存斌 康立荣 《东南大学学报(自然科学版)》 北大核心 2026年第2期191-201,共11页
软土地基变形大且强度低,工程中常采用桩基复合地基进行地基加固处理,其中刚柔性复合桩复合地基以其承载控沉能力强、成本低的特性而得到广泛应用。本文首先介绍了国内典型刚柔性复合桩的复合方式及施工方法,其次针对其中一种典型刚柔... 软土地基变形大且强度低,工程中常采用桩基复合地基进行地基加固处理,其中刚柔性复合桩复合地基以其承载控沉能力强、成本低的特性而得到广泛应用。本文首先介绍了国内典型刚柔性复合桩的复合方式及施工方法,其次针对其中一种典型刚柔性复合桩——内芯高强度(钢筋)混凝土预制管桩与外芯水泥土搅拌桩复合,从施工效应、多界面效应以及承载特性3个方面进行综述,对比分析国内外研究现状,总结刚柔性复合桩在挤土与挤桩效应、同轴效应、内外界面效应、抗压抗拔承载能力、沉降设计方法等方面当前的研究成果。最后,指出复合桩在挤桩效应、同轴效应以及水平承载力设计等方面的未来研究方向和技术对策,为刚柔性复合桩技术发展和工程应用提供参考和依据。 展开更多
关键词 刚柔性复合桩 承载性能 多界面效应 挤土效应 同轴性
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琼东南陵水构造64/07区块地层压力分布规律研究
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作者 邱康 王利华 +3 位作者 崔强 王颖 王孝山 熊振宇 《油气藏评价与开发》 北大核心 2026年第1期206-215,共10页
南海琼东南盆地异常高压成因机理复杂,造成钻前压力预测难度大、精度低,严重影响了钻探安全。以琼东南盆地陵水构造64/07区块为研究对象,从构造演化、加卸载机制等方面分析,揭示了该区块异常高压耦合成因机制,针对性创建了多机制耦合压... 南海琼东南盆地异常高压成因机理复杂,造成钻前压力预测难度大、精度低,严重影响了钻探安全。以琼东南盆地陵水构造64/07区块为研究对象,从构造演化、加卸载机制等方面分析,揭示了该区块异常高压耦合成因机制,针对性创建了多机制耦合压力预测方法,并建立了已钻井地层压力剖面及区域地层压力三维模型,系统分析了该区块纵、横向压力体系。研究结果表明:该区域地层高压成因黄流组以上为欠压实成因,梅山组以下为欠压实与流体充注耦合成因。纵向上,莺歌海组中下部压力开始抬升,黄流组为压力过渡带,梅山组与三亚组进入超压带,最高压力系数可达2.10;横向上看,整体呈现“西低东高”“北低南高”特征,相关研究成果在L5-1井进行了应用。该方法核心在于针对梅山组地层压力耦合成因,建立了多参数有效应力法,引入下部高压层泥质含量、孔隙度及有效应力等参数,避开原始沉积加载及后续卸载这一不易确定的难题,实现了储层高压的精准预测。运用该方法钻前预测地层压力平均精度为87.1%,在实钻过程中,根据测井及测试数据,及时修正预测结果,下部地层压力预测精度提高至98.8%,满足了钻井设计及现场施工要求。 展开更多
关键词 琼东南盆地 陵水构造 异常高压 异常压力机理 多参数有效应力法
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低温多效海水淡化设备停运保养技术研究
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作者 郑海超 王丙贵 +2 位作者 王磊 陈愿媛 贾婷婷 《东北电力技术》 2026年第1期49-53,共5页
某海滨电厂低温多效海水淡化设备蒸发器发生泄漏,对4台海水淡化设备运行方式进行检查,采用间断运行方式的海水淡化设备腐蚀泄漏问题较为突出。因设备停运期间,内部湿度大,局部区域含盐量高,停运期间保养措施不当会造成蒸发器换热管发生... 某海滨电厂低温多效海水淡化设备蒸发器发生泄漏,对4台海水淡化设备运行方式进行检查,采用间断运行方式的海水淡化设备腐蚀泄漏问题较为突出。因设备停运期间,内部湿度大,局部区域含盐量高,停运期间保养措施不当会造成蒸发器换热管发生腐蚀,严重时会导致腐蚀穿孔,造成蒸发器泄漏。为此,分析了其现有停运保养措施的合理性,并提出了改进,采用干风保养技术,保证设备停运期间环境湿度低于40%,可以有效抑制铝黄铜材质换热管在高温高湿环境下发生腐蚀泄漏问题。 展开更多
关键词 海水淡化设备 低温多效 设备腐蚀 停运保养
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页岩储层限流射孔高效起裂机理
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作者 朱柏宇 王大江 +3 位作者 李奎东 肖佳林 朱志芳 张凡 《断块油气田》 北大核心 2026年第1期170-176,共7页
水平井分段多簇压裂是目前非常规储层开发的有效手段,但往往面临着非均衡起裂扩展的问题。限流射孔通过限制段内射孔数,进而提高射孔摩阻,已经被光纤监测、示踪剂监测等手段验证能够提高多簇裂缝起裂均衡程度。然而,限流射孔裂缝几何形... 水平井分段多簇压裂是目前非常规储层开发的有效手段,但往往面临着非均衡起裂扩展的问题。限流射孔通过限制段内射孔数,进而提高射孔摩阻,已经被光纤监测、示踪剂监测等手段验证能够提高多簇裂缝起裂均衡程度。然而,限流射孔裂缝几何形态与控制因素仍不明确。以涪陵气田JY-A为例,采用三维离散格子法对射孔簇尺度三维水力裂缝起裂行为、规律及模式进行了研究,并进一步分析了裂缝起裂的影响因素。结果显示:1)不同孔眼水力裂缝扩展的呼吸效应与光纤监测结果一致;2)由于射孔簇多点起裂,存在单孔多缝模式;3)射孔数为3~4时水力裂缝起裂较为均衡,180°水平射孔起裂最为均匀。在该结果基础上摒弃传统“分段分簇”射孔模式,提出“全段均衡限流射孔”压裂工艺思路。该研究为非常规油气分段多簇裂缝扩展提供了不同尺度的视角,有助于现场极限限流射孔方法的设计。 展开更多
关键词 水力压裂 限流射孔 三维格子法 呼吸效应 多点起裂 分段分簇
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Multi-effect anthraquinone-based polyimide enclosed SnO_(2)/reduced graphene oxide composite as high-performance anode for lithium-ion battery
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作者 Lin Wang Yinjie Kuang +4 位作者 Qian Cui Junyu Shi Liubin Song Qionghua Li Tianjian Peng 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2023年第9期1231-1243,共13页
The cycling stability of SnO_(2)anode as lithium-ion battery is poor due to volume expansion.Polyimide coatings can effectively confine the expansion of SnO_(2).However,linear polyimides are easily dissolved in ester ... The cycling stability of SnO_(2)anode as lithium-ion battery is poor due to volume expansion.Polyimide coatings can effectively confine the expansion of SnO_(2).However,linear polyimides are easily dissolved in ester electrolytes and their carbonyls is not fully utilized during charging/discharging process.Herein,the SnO_(2)enclosed with anthraquinone-based polyimide/reduced graphene oxide composite was prepared by self-assembly.Carbonyls from the anthraquinone unit provide fully available active sites to react with Li^(+),improving the utilization of carbonyl in the polyimide.More exposed carbonyl active sites promote the conversion of Sn to SnO_(2)with electrode gradual activation,leading to an increase in reversible capacity during the charge/discharge cycle.In addition,the introduction of reduced graphene oxide cannot only improve the stability of polyimide in the electrolyte,but also build fast ion and electron transport channels for composite electrodes.Due to the multiple effects of anthraquinone-based polyimide and the synergistic effect of reducing graphene oxide,the composite anode exhibits a maximum reversible capacity of 1266 mAh·g^(−1) at 0.25 A·g^(−1),and maintains an excellent specific capacity of 983 mAh·g^(−1) after 200 cycles.This work provides a new strategy for the synergistic modification of SnO_(2). 展开更多
关键词 anthraquinone-based polyimide multi-effect tin dioxide reduced graphene oxide lithium-ion battery
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北京卫星网络产业的创新辐射效应
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作者 沈映春 周昕怡 李娓 《科技智囊》 2026年第1期18-27,共10页
[研究目的]卫星网络产业是我国战略性新兴产业的重要组成部分,而北京作为卫星网络产业的主阵地,对于全国卫星网络产业的创新发展具有辐射带动作用。揭示北京对各省(区、市)卫星网络产业的多维创新辐射效应及其影响机制,有助于卫星网络... [研究目的]卫星网络产业是我国战略性新兴产业的重要组成部分,而北京作为卫星网络产业的主阵地,对于全国卫星网络产业的创新发展具有辐射带动作用。揭示北京对各省(区、市)卫星网络产业的多维创新辐射效应及其影响机制,有助于卫星网络产业更好地促进经济高质量发展,增强国家综合国力。[研究方法]借鉴静电场理论构建卫星网络产业创新辐射场模型,分别对2016—2023年在地理、经济和技术断裂点距离下,北京对除西藏、中国香港、中国澳门、中国台湾地区外的29个省(区、市)卫星网络产业产生的辐射效应进行测算和分析,并以基于多维距离的北京创新辐射力为核心解释变量、卫星网络产业的创新绩效为被解释变量,构建面板数据进行回归分析。[研究结论] 2023年各省(区、市)受到的辐射强度较2016年明显增强;不同距离下不同省(区、市)受到的创新辐射力有所差异。各省(区、市)卫星网络产业创新绩效受北京辐射效应的正向影响,且影响程度因距离的不同而变化,其中,基于地理距离的创新辐射力对产业创新绩效提升的影响最大,其次是基于经济距离的创新辐射力。城乡收入差距更小、一般预算支出更高的省(区、市)受到的北京创新辐射效应更强。为推动全国卫星网络产业高质量发展,北京应充分发挥领军作用,深度对接津冀地区,加强南北联动,赋能中西部地区。 展开更多
关键词 卫星网络产业 创新辐射效应 静电场力模型 多维距离 创新绩效
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基于同群效应的企业集群式创新博弈演化多主体仿真研究
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作者 张应青 范如国 +1 位作者 罗明 朱超平 《计算机工程与应用》 北大核心 2026年第1期369-378,共10页
产业集群创新、关键核心技术创新和复杂产品协同创新是集群式创新的重要表现形式,理解其形成机制和影响过程对于推动创新实践至关重要。通过采用多主体仿真分析方法,构建具有“小世界”特性和多群体特征的集群式创新网络,结合Cournot和S... 产业集群创新、关键核心技术创新和复杂产品协同创新是集群式创新的重要表现形式,理解其形成机制和影响过程对于推动创新实践至关重要。通过采用多主体仿真分析方法,构建具有“小世界”特性和多群体特征的集群式创新网络,结合Cournot和Stackelberg博弈,建立包含自主创新、模仿跟随和混合式创新情形的复杂网络演化模型,系统分析了同群效应下知识产权保护、专利费用、创新风险及创新网络结构对集群式创新行为的影响。研究表明,在良好的创新环境中,同群效应能够显著促进集群式创新行为,而提高知识产权保护力度、合理设定专利费用及优化网络结构可进一步强化同群效应的积极作用,为创新实践提供了理论支持。 展开更多
关键词 多主体仿真 同群效应 集群式创新行为 演化博弈
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道路绿地植被对空气质量及热环境影响研究进展
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作者 张诚 圣倩倩 祝遵凌 《风景园林》 北大核心 2026年第1期47-55,共9页
【目的】在全球气候变化与快速城市化双重压力下,热岛效应和空气污染已成为突出的城市环境问题。道路绿地植被作为绿色基础设施的重要组成部分,在遮阴降温、污染物沉降及局地气候调节方面具有显著潜力。然而,道路绿地植被生态效益的发挥... 【目的】在全球气候变化与快速城市化双重压力下,热岛效应和空气污染已成为突出的城市环境问题。道路绿地植被作为绿色基础设施的重要组成部分,在遮阴降温、污染物沉降及局地气候调节方面具有显著潜力。然而,道路绿地植被生态效益的发挥,具有多维度和多机制的复杂性,需权衡其间的关系。【方法】本研究从植被个体特征、植物群落特征以及环境背景3个维度构建综合分析框架,阐明道路绿地植被在改善空气质量与调节热环境中的协同与拮抗机制。【结果】研究表明:1)道路绿地植被对空气质量及热环境的影响具有多维度特征,其作用效果由叶片微观形态到冠层宏观结构,再到群落配置的多级特征的综合作用决定;2)道路绿地植被在空气质量改善与热环境调节两类生态功能上存在内在机制冲突,需依据道路污染水平、风热环境及盛行气象条件进行多目标权衡,并通过精细化调控植被三维结构,协同提升空气质量与行人热舒适性;3)街道高宽比、朝向和风环境等环境背景是植被发挥生态效益的制约因素,道路绿地植被设计须遵循“因地制宜”原则,依据具体背景环境特征进行差异化配置。【结论】未来应探索道路绿地植被三维空间形态的量化体系,融合多源监测与模拟技术,揭示植被结构对热效应与污染物扩散的复合影响机制,为可持续、多目标和综合型道路景观设计与生态宜居城市构建提供理论支撑。 展开更多
关键词 风景园林 植被特征 道路绿化 生态效益 绿色基础设施 空气污染 热岛效应 多尺度
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绿色技术转移的空间特征及其碳全要素生产率改进效应
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作者 刘程军 刘梦甜 +4 位作者 张世豪 张博盛 张君婷 陈国亮 蒋天颖 《地理科学》 北大核心 2026年第2期412-424,共13页
实现碳中和背景下低碳经济转型与绿色增长是中国当前面临的重大问题之一。研究基于2010―2020年的绿色专利交易数据,系统刻画了不同地理尺度下中国282个城市绿色技术转移的地理分布格局和空间关联特征,并考察了不同尺度、多维邻近下绿... 实现碳中和背景下低碳经济转型与绿色增长是中国当前面临的重大问题之一。研究基于2010―2020年的绿色专利交易数据,系统刻画了不同地理尺度下中国282个城市绿色技术转移的地理分布格局和空间关联特征,并考察了不同尺度、多维邻近下绿色技术转移对碳全要素生产率变动程度的影响。研究结果表明:(1)省市两级同区域内的绿色技术转移主要发生在东部沿海的核心城市和中西部省会城市,其中东部核心城市对周边区域的辐射作用较强,而中西部省会城市带动作用相对较弱;(2)绿色技术转移网络呈现“核心-边缘”特征,东部地区网络联系密集且中西部稀疏,“上海-深圳”“北京-天津”等“强强”节点和“上海-盐城(江苏)”“苏州-宣城(安徽)”等“强弱”节点联系均较为频繁,基本形成了京津冀、长三角、珠三角与成渝地区的四边形格局;(3)绿色技术的转移、产业结构的高级化及市场化程度的提高有利于区域碳全要素生产率的正向变动;(4)空间尺度的缩小和地理距离、行政辖区及资源禀赋等多维空间的邻近对碳全要素生产率的提升具有正向促进作用。 展开更多
关键词 绿色技术转移 碳全要素生产率 多维邻近 尺度效应
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面向有效需求的居民体育消费潜力多维测度:理论框架与实证检验
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作者 赵胜国 王健 《体育学刊》 北大核心 2026年第1期83-91,共9页
基于有效需求理论的梳理,辨析体育消费潜力的概念框架,构建居民体育消费潜力指标体系,并采用熵值法通过结合2015—2023年我国居民体育消费潜力的多维数据进行实证研究。结果表明:(1)现阶段我国居民体育消费潜力指标体系主要包括由体育... 基于有效需求理论的梳理,辨析体育消费潜力的概念框架,构建居民体育消费潜力指标体系,并采用熵值法通过结合2015—2023年我国居民体育消费潜力的多维数据进行实证研究。结果表明:(1)现阶段我国居民体育消费潜力指标体系主要包括由体育消费需要、体育消费能力和体育消费环境3个维度构成的一级指标,体育消费的需要主体、需要客体、支付能力、参与能力、社会环境和市场环境6个要素构成的二级指标,以及29个具体指标测项。该指标体系能有效测度和对比不同年度居民体育消费潜力之间的具体水平及主要问题。(2)2015—2023年我国居民体育消费潜力总体呈现平稳性上升趋势,但纵向不同阶段的动力因素呈现典型的动态变化轨迹,以及横向不同维度内部要素之间存在明显的动力支撑差异。研究建议分区域、分层级推广应用该测度指标,分维度、分要素精准施策推动居民体育消费潜力有效释放。 展开更多
关键词 体育消费潜力 多维测度 动力要素 有效需求
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