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Pressure and temperature effects resulting from impact onto materials of different reactivity
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作者 Andreas Heine Matthias Wickert 《Defence Technology(防务技术)》 2025年第2期221-230,共10页
The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale setup.This allows deriving qualitative information on the occurrin... The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale setup.This allows deriving qualitative information on the occurring phenomenology as well as quantitative statements about the relative effects sizes as a function of target material and threat.The considered target materials are steel,aluminum,and magnesium.As threats,kinetic energy penetrator,explosively formed projectile,and shaped charge jet are used.For the investigated combinations,the measured overpressures vary by a factor of up to 5 for a variation of the material,by a factor of up to 7 for a variation of the threat,and by a factor larger than 15for a simultaneous variation of both.The obtained results as well as the experimental approach are relevant for the basic understanding of impact effects and risks due to material reactivity.The paper combines two main aims.Firstly,to provide a summary of own prior work in a coherent journal article and,secondly,to review and discuss these earlier results with a new perspective. 展开更多
关键词 impact effects PRESSURE TEMPERATURE Risk assessment Material reactivity
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Opportunities to Improve the Quality of Environmental Reports and the Effectiveness of Environmental Impact Assessment: A Case of Electric Power Transmission Systems in Brazil
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作者 Vinícius Arthico Demori Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期124-140,共17页
A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international l... A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international literature has contributed to the understanding of the essential aspects to be verified regarding the quality of EIS, offering a wide spectrum of good practice examples related to the content of the studies. Even so, there is a need for empirical studies that allow the identification of specific aspects related to the context of application of the EIS, which could lead to the identification of opportunities to improve both the quality of the reports and also the effectiveness of EIA. Therefore, the present paper is focused on the quality review of a number of EIS submitted to the Brazilian Federal Environmental Agency (Ibama) to instruct the assessment of electric power transmission systems. Based on the application of the EIS quality review package as proposed by Lee and Colley (1992), the outcomes reveal opportunities for improving the scope of EIA, analysis of alternatives, prediction of magnitude and the assessment of impact significance. Finally, the development and/or adaptation of a similar tool for the systematic review of the quality of EIA reports is recommended. 展开更多
关键词 Environmental impact Assessment effectIVENESS Electric Energy Transmission Systems
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Reformed Environmental Impact Assessment in China: An Evaluation of Its Effectiveness
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作者 Yang Yang 《Journal of Environmental Protection》 2020年第10期889-908,共20页
Since 2015, a “reform storm” of Environmental Impact Assessment (EIA) opened up in China. This study tries to answer the question of whether these reforms improve the effectiveness of EIA. First, we elaborate on the... Since 2015, a “reform storm” of Environmental Impact Assessment (EIA) opened up in China. This study tries to answer the question of whether these reforms improve the effectiveness of EIA. First, we elaborate on the reforms along with three well-acknowledged components, including EIA legislation, administration, and process. Then, evaluate the reformed EIA system against revised Ahmad and Wood’s criteria. The results demonstrate that the revised laws and regulations are more stringent than the old versions. The EIA process is simplified, and its coordination with the pollutant discharge permit system is promoted. The interim and post-event supervision is currently more robust and the penalties are more severe than before. However, the hierarchical position of the Environmental Protection Law is not high enough and the coordination of different government departments is still challenging. In summary, despite the problems occurring at the initial phase of reforms, the effectiveness of the EIA system has largely been improved. 展开更多
关键词 Environmental impact Assessment REFORM EVALUATION effectIVENESS
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Effects on Sedimentary Processes via Upper Triassic Climate Forcing Caused by Multiple Impacting and Large Igneous Provinces (LIP)-Rifting/Degassing: Jordanian Platform/Arabian Plate and Germanic Basin/Central Europe
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作者 Werner Schneider Elias Salameh 《Open Journal of Geology》 CAS 2023年第2期136-170,共35页
Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies t... Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies types, unconformities, flash flood deposits, maximum flooding surfaces/sequence boundary (MFS/SB), mineralogy, and isotope anomalies. Further, Moon recession and changes of Earth’s rotation velocity (core/mantle boundary) are associated with multiple impacting and large igneous provinces/Mid Oceanic Ridge Basalt, LIP/MORB-rifting/degassing. While acidification (by degassing, sturz-rain) does influence tectosilicates and carbonates, montmorillonite represents a key mineral as transformation of volcanic/impact glass (Tephra) to be found as co-components in and in certain pelite units as “boundary clay-suspicions” (mixture of eolian paleoloess, pelite, paleosol, and tephra → tuffite). Obviously, unconformities and sequence boundaries of both study areas separate and dislocate interrupted ∂<sup>13</sup>C and <sup>87</sup>Sr/<sup>86</sup>Sr-data groups along the isotope curves. Both Proto-Arctic Ocean rifting/degassing comprising kimberlitic pyroclastic eruptions and Neotethys rifting/degassing as well as multiple impacting played the most important role during the Norian, followed by the incipient Central Atlantic Magmatic Provinces rifting since the Rhaetian. The following associations are encountered and dealt with in this study: Sequence boundaries-∂<sup>13</sup>C, maximum flooding surfaces-(FUCs)-∂<sup>13</sup>C, unconformities-plate motion, tephra-pelite-tuffite-montmorillonite. Norian: maximum flooding surfaces (MFSs)-“paleosol”/boundary clay?-rifting-volcanism, Moon/Earth data change. So the Norian (~221 - 206 Ma) hosts anomalous “amalgamated maximum flooding surfaces (MFSs)”, amalgamated paleosol (Jordanian Platform), multiple impacting (~219 - 214 Ma), the maximum opening of the Proto-Arctic Ocean (PAO) (~230 - 200 Ma), Neo-Tethys (NT)-subvolcanic (sills, dikes) in the NE Dead Sea area prior the Rhaetian, and a significant change of Earth/Moon relation data. The study concludes that rare and extreme events are very strongly shaping the geologic constellations in the Earth System. 展开更多
关键词 Endogenic and impact Drivers Sedimentary effects Interplay Processing Event-Stratigraphy
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强震下基础隔震结构软碰撞防护研究
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作者 金建敏 刘彦辉 +1 位作者 陈鹏 周惠蒙 《世界地震工程》 北大核心 2025年第1期165-174,共10页
针对基础隔震结构在超罕遇地震的强震作用下隔震层位移超限问题,采用已有弹性软碰撞防护装置和所研发的弹塑性软碰撞防护装置。考虑上部结构非线性,建立设置两类软碰撞防护装置的基础隔震结构模型,进行不同地震设防水准地震作用下设置... 针对基础隔震结构在超罕遇地震的强震作用下隔震层位移超限问题,采用已有弹性软碰撞防护装置和所研发的弹塑性软碰撞防护装置。考虑上部结构非线性,建立设置两类软碰撞防护装置的基础隔震结构模型,进行不同地震设防水准地震作用下设置两类软碰撞防护装置的基础隔震结构的非线性时程分析,研究不同防护距离、不同力学性能参数的弹性及弹塑性软碰撞防护装置对隔震层限位效果及上部结构地震响应的影响。结果表明:在超罕遇地震的强震作用下,两类软碰撞防护装置均可起到限制隔震层位移的作用;与仅能为隔震层附加刚度的弹性软碰撞装置相比较,能够为隔震层同时附加刚度和阻尼力的弹塑性软碰撞防护装置,隔震层限位效果和上部结构层间位移角响应控制效果均较优。合理设置弹性及弹塑性软碰撞防护装置,在将隔震层位移限制在规范限值以内的同时,上部结构最大加速度可限制在地震波输入峰值50%以下,确保基础隔震结构发挥正常的隔震功能。 展开更多
关键词 基础隔震结构 隔震层位移 软碰撞防护 限位效果 地震响应
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Environmental Impact Assessment Follow-Up of Seismic Survey Offshore Activities in Brazil
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作者 Fontes Nuno Eduardo Paulo Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期141-155,共15页
Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest f... Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest from scientists and practitioners, though it is recognized as one of the weakest points of EIA systems globally. Also, EIA follow-up is influenced by the context, mainly in terms of the types of projects or activities and their related impacts on the environment. Therefore, the present paper is focused on the investigation of the follow-up stage applied to the activity of seismic survey coupled with offshore oil & gas exploitation in Brazil. Research was based on a qualitative approach that included document analysis and semi-structured interviews with analysts involved in EIA processes, and sought to generate evidence of effectiveness of the EIA follow-up as conducted by the Federal Environment Agency (Ibama) in order to situate the practice of follow-up in the broader context of international best practice principles. Based on the findings, it was concluded that, due to the peculiarities of offshore seismic survey, it is necessary to promote adaptations in the procedures for monitoring impacts in order to ensure proper alignment with the principles and conceptual foundations that guide EIA practice. Specifically, the timing of the execution of the activity imposes challenges for its integration into the “conventional” cycle that has guided the monitoring of the impacts in the EIA of projects. 展开更多
关键词 Environmental impact Assessment Follow-Up Follow-Up effectiveness Oil and Gas Offshore Seismic Survey
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环境保护税对农产品批发市场价格的影响
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作者 杨肖丽 余瑞 景再方 《中国流通经济》 北大核心 2025年第3期21-32,共12页
农产品批发市场作为农产品流通的关键环节,其价格波动备受学界和政府关注。本文从我国环境保护税的角度关注政策实施对农产品批发市场价格的影响,旨在为稳定农产品批发价格,推动农产品批发市场的可持续发展提供政策依据。近年来,我国猪... 农产品批发市场作为农产品流通的关键环节,其价格波动备受学界和政府关注。本文从我国环境保护税的角度关注政策实施对农产品批发市场价格的影响,旨在为稳定农产品批发价格,推动农产品批发市场的可持续发展提供政策依据。近年来,我国猪肉价格波动明显,而2018年实施的《中华人民共和国环境保护税法》对高污染的养猪业造成巨大冲击,引起猪肉价格再次大幅波动。因此,聚焦我国环保税,以猪肉批发市场价格为例,探究环保税对农产品批发市场价格的短期和长期影响。考虑各省实施环保税的时间和地区差异,选取云南省、山东省和湖北省三个猪肉主产省作为样本地区构建准自然实验,采用双重差分方法,实证检验环保税政策对猪肉价格的长短期影响。研究发现,环保税政策的实施导致猪肉价格短期上涨,且波动幅度较大,但长期呈现稳定趋势。排除年份和节假日影响后,结果仍然稳健可靠。表明随着环保技术的不断投入,养殖户完成了生产技术和市场结构调整等一系列适应过程,有助于降低长期的环境治理成本,且能稳定农产品批发价格,实现农产品批发市场的可持续发展。据此,应加强对农产品批发市场的环保资金和政策支持,建立农产品批发价格应急调控机制,建立健全横向补偿机制,因地制宜调整政策实施进度。 展开更多
关键词 长短期影响 双重差分 动态效应 环境保护税
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绿色金融助推乡村振兴:理论逻辑与实证检验
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作者 刘茜 潘金萍 《吉林工商学院学报》 2025年第1期96-104,128,共10页
全面推进乡村振兴是我国的重大和长期战略目标,实现这一目标过程离不开绿色发展。适应农村经济特性的绿色金融,将成为推动乡村振兴并实现可持续绿色发展的关键创新力量。基于2011—2021年我国30个省份的面板数据实证研究绿色金融对乡村... 全面推进乡村振兴是我国的重大和长期战略目标,实现这一目标过程离不开绿色发展。适应农村经济特性的绿色金融,将成为推动乡村振兴并实现可持续绿色发展的关键创新力量。基于2011—2021年我国30个省份的面板数据实证研究绿色金融对乡村振兴的影响,研究表明:乡村振兴具有空间集聚特征,并且绿色金融对乡村振兴具有显著的本地驱动效应和空间溢出效应;绿色金融对乡村振兴的促进作用存在空间区域异质性特征,东部地区绿色金融对乡村振兴的影响效果最为显著;绿色金融对乡村振兴的影响不是始终不变的,而是呈非线性关系,会随着时空的变化而发生改变。 展开更多
关键词 绿色金融 乡村振兴 空间溢出效应 非线性影响
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Numerical Analysis and Verification of the Gas Jet from Aircraft Engines Impacting a Jet Blast Deflector 被引量:4
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作者 Fu-Dong Gao De-Xin Wang +1 位作者 Hai-Dong Wang Ming-Ming Jia 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第5期127-137,共11页
The process of the gas jet from aircraft engines impacting a jet blast deflector is not only a complex fluid–solid coupling problem that is not easy to compute, but also a safety issue that seriously interferes with ... The process of the gas jet from aircraft engines impacting a jet blast deflector is not only a complex fluid–solid coupling problem that is not easy to compute, but also a safety issue that seriously interferes with flight deck envi?ronment. The computational fluid dynamics(CFD) method is used to simulate numerically the impact e ect of gas jet from aircraft engines on a jet blast deflector by using the Reynolds?averaged Navier?Stokes(RANS) equations and turbulence models. First of all, during the pre?processing of numerical computation, a sub?domains hybrid meshing scheme is adopted to reduce mesh number and improve mesh quality. Then, four di erent turbulence models includ?ing shear?stress transport(SST) k-w, standard k-w, standard k-ε and Reynolds stress model(RSM) are used to compare and verify the correctness of numerical methods for gas jet from a single aircraft engine. The predicted values are in good agreement with the experimental data, and the distribution and regularity of shock wave, velocity, pressure and temperature of a single aircraft engine are got. The results show that SST k?w turbulence model is more suitable for the numerical simulation of compressible viscous gas jet with high prediction accuracy. Finally, the impact e ect of gas jet from two aircraft engines on a jet blast deflector is analyzed based on the above numerical method, not only the flow parameters of gas jet and the interaction regularity between gas jet and the jet blast deflector are got, but also the thermal shock properties and dynamic impact characteristics of gas jet impacting the jet blast deflector are got. So the dangerous activity area of crew and equipments on the flight deck can be predicted qualitatively and quantitatively. The proposed research explores out a correct numerical method for the fluid–solid interaction during the impact process of supersonic gas jet, which provides an e ective technical support for design, thermal ablation and structural damage analysis of a new jet blast deflector. 展开更多
关键词 Aircraft engine Gas jet Computational fluid dynamics Jet blast deflector impact effect
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超声振动塑性机理及本构建模研究进展
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作者 钟斌 王元龙 +2 位作者 张传伟 肖力 谢佳昊 《精密成形工程》 北大核心 2025年第1期164-182,共19页
超声振动辅助成形技术是一项能场与物理场交叉的新兴绿色成形技术,因其可显著提高材料成形质量、减少材料成形缺陷,被广泛应用于材料加工领域。目前研究普遍认为,致使材料流动应力下降的体积效应与降低界面摩擦的表面效应是声塑性效应... 超声振动辅助成形技术是一项能场与物理场交叉的新兴绿色成形技术,因其可显著提高材料成形质量、减少材料成形缺陷,被广泛应用于材料加工领域。目前研究普遍认为,致使材料流动应力下降的体积效应与降低界面摩擦的表面效应是声塑性效应的主要作用机制。概述了超声振动辅助拉拔、拉深、渐进成形等先进成形工艺的原理,总结了3种典型超声塑性成形工艺的特点和研究进展。在此基础上,综述了超声振动辅助塑性机理下的应力叠加效应、声软化效应、残余效应以及动态冲击效应等体积塑性机制以及矢量效应与局部热效应的表面塑性机制,并分别对超声振动辅助体积塑性机制与表面塑性机制的研究进展进行了总结。其次,重点从体积效应和表面效应2个方面综述了超声振动辅助塑性成形本构模型,并从唯象模型和物理模型两方面总结了体积效应下本构模型的研究现状,同时总结了表面效应下摩擦模型的研究进展。最后归纳了超声振动辅助成形机理应用中存在的问题并对发展方向进行了展望。 展开更多
关键词 超声振动辅助 塑性成形 体积效应 表面效应 动态冲击效应 本构建模
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武装直升机机载空地导弹发射过程燃气冲击效应研究
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作者 胡可镇 卓长飞 +1 位作者 纪元 蒋显松 《兵工自动化》 北大核心 2025年第1期82-89,共8页
为研究武装直升机机载空地导弹发射过程对机体造成的动力冲击效应,采用分块混合网格模型并结合3维非定常Navier-Stokes方程与动网格方法,开展武装直升机机载空地导弹发射起始过程的燃气射流冲击流场的计算,并对比近机身蒙皮发射工况与... 为研究武装直升机机载空地导弹发射过程对机体造成的动力冲击效应,采用分块混合网格模型并结合3维非定常Navier-Stokes方程与动网格方法,开展武装直升机机载空地导弹发射起始过程的燃气射流冲击流场的计算,并对比近机身蒙皮发射工况与近机翼翼梢发射工况下载机使用外挂导轨式结构受流场冲击的影响。计算结果表明:2个工况的起始冲击波流场发展过程相似,超压分布均为单峰函数,但近机身蒙皮发射工况下机身处的超压正压峰值与负压峰值明显更大;近机翼翼梢发射载弹对发射架在各方向上产生的最大冲击载荷相对于近机身蒙皮发射载弹的变化率较大,燃气起始冲击波对壁面的超压载荷及各向冲击力与发射方案、发射载弹附近直升机迎气面积、载弹距机身蒙皮距离、载弹距机翼翼梢距离有很大相关性。 展开更多
关键词 武装直升机 机载空地导弹 外挂导轨式 燃气射流 冲击效应 超压
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120 t转炉五孔氧枪喷头优化设计研究
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作者 袁建都 刘坤 +3 位作者 冯亮花 段华天 刘文娟 张淑萍 《冶金能源》 北大核心 2025年第1期15-21,共7页
针对国内某钢厂120 t转炉氧枪供氧强度低、吹炼时间长、化渣慢、寿命短等问题,对其五孔氧枪喷头倾角进行优化设计。基于数值模拟软件FLUENT,在冷态下(300 K)分析了喷头倾角对射流特性的影响,并在炼钢温度下(1873 K)进一步对比新旧氧枪... 针对国内某钢厂120 t转炉氧枪供氧强度低、吹炼时间长、化渣慢、寿命短等问题,对其五孔氧枪喷头倾角进行优化设计。基于数值模拟软件FLUENT,在冷态下(300 K)分析了喷头倾角对射流特性的影响,并在炼钢温度下(1873 K)进一步对比新旧氧枪喷头的射流特性。结果表明:在冷态下,随着喷头倾角增加,射流独立性改善;当喷头倾角11°时,有效冲击面积最大;当喷头倾角12°时,化渣面积最大;最佳操作枪位为40 D_(e),综合考虑最佳喷头倾角为12°。在炼钢温度下,与旧喷头相比,新喷头的超音速区域长度增加1.0 D_(e),冲击深度更大,有效冲击面积增大6.67%,化渣面积增大10.39%,喷头出口负压更小,使用寿命更长。 展开更多
关键词 转炉氧枪 喷头倾角 有效冲击面积 化渣面积 数值模拟
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“一带一路”背景下目的国海外仓建设对跨境电商出口影响的实证研究
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作者 周梅 《哈尔滨学院学报》 2025年第1期42-47,共6页
文章在“一带一路”背景下研究目的国海外仓对跨境电商出口的影响,选取46个国家2017-2021年的数据展开实证分析,考虑到各国之间的物流水平有所差异,将进一步引入物流绩效水平指标作为调节变量,研究海外仓建设在不同物流绩效水平国家中... 文章在“一带一路”背景下研究目的国海外仓对跨境电商出口的影响,选取46个国家2017-2021年的数据展开实证分析,考虑到各国之间的物流水平有所差异,将进一步引入物流绩效水平指标作为调节变量,研究海外仓建设在不同物流绩效水平国家中对跨境电商出口的影响效应。研究结果表示,物流绩效水平越高的国家,海外仓建设对跨境电商出口的影响更为显著。因此,中国海外仓建设需加紧进程,利用技术管理海外仓运作,加强与沿线国家的经贸合作,尽快形成电商规模效应。 展开更多
关键词 一带一路 海外仓 跨境电商出口 影响效应
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滇中地区地表温度时空分布及其驱动因子分析
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作者 廖朝莲 周鹏飞 +1 位作者 叶江霞 周汝良 《广西师范大学学报(自然科学版)》 北大核心 2025年第1期185-200,共16页
地表温度(LST)是影响陆地和大气间能量交换和水分循环的重要因素,在干旱、冻害、森林防火等灾害监测中起关键作用。基于2000—2020年LST数据,通过GIS空间分析、多环缓冲区以及地理探测器等手段,对滇中地区年、季、月、昼夜的年均LST空... 地表温度(LST)是影响陆地和大气间能量交换和水分循环的重要因素,在干旱、冻害、森林防火等灾害监测中起关键作用。基于2000—2020年LST数据,通过GIS空间分析、多环缓冲区以及地理探测器等手段,对滇中地区年、季、月、昼夜的年均LST空间分布特征及变化趋势进行分析,并结合多源遥感数据对年均LST的关键影响因子进行探讨。结果表明:1)地表温度年均、年均白天及年均夜晚在空间分布上表现为滇中东北部较低,西南部较高,三者均呈升温趋势,且年均夜晚变化率最大(0.043 4℃·a^(-1));年均的季节变化率为夏季>秋季>春季>冬季;年均LST以6月为中点呈现年内强对称规律,最低值在12月,最高值在6月;2)气温、DEM、DSR、DNMI、NDVI是LST的主要影响因子,且气温和DEM与其他影响因子交互作用时对LST的解释力极度增强;滇中地区海拔每升高100 m,年均、年均白天及年均夜晚LST分别下降0.48、0.46、0.49℃;不同下垫面的年均LST为建设用地>耕地>草地>林地>水域;在所取圆环面积内城市热岛效应强度为蒙自市>楚雄市>红塔区>麒麟区,五华区属于城市冷岛效应。滇中地区地表温度的空间格局分析可以为该区农业及消防事业规划提供一定的理论支撑。 展开更多
关键词 滇中地区 地表温度 空间分布 地理探测器 热(冷)岛效应 影响因子
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An Empirical Analysis on the Impacting of Fiscal Policy on Haze Governance :Based on the Data of Anhui Province from 2005 to 2014 被引量:1
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作者 田时中 费慧心 +1 位作者 万梦珺 许玖瑶 《石家庄经济学院学报》 2016年第3期78-84,共7页
为准确把握财政政策对雾霾治理的影响,在确立财政政策投入和雾霾治理产出两个维度的基础上,建立评价指标体系,选取安徽省2 0 0 5 年-2 0 1 4 年评价数据,建立T0 P S IS模型,进行实证评价.结果表明:总体上,安徽省财政政策对雾霾治理影... 为准确把握财政政策对雾霾治理的影响,在确立财政政策投入和雾霾治理产出两个维度的基础上,建立评价指标体系,选取安徽省2 0 0 5 年-2 0 1 4 年评价数据,建立T0 P S IS模型,进行实证评价.结果表明:总体上,安徽省财政政策对雾霾治理影响效应表现逐年削弱的变化特征.其次,分阶段来看,2 0 1 0年以前,安徽省财政政策对雾霾治理的影响出现“W ” 型变化特征,即“削弱-增强-削弱-增强” 的变化.2 0 1 1年-2 0 1 3年财政政策效果快速下降;2 0 1 4年以来,财政政策对雾霾治理的影响有增强的趋势.再次,财政资金使用不科学,技术创新不足一定程度上削弱了财政政策对雾霾治理的影响效应.为进一步增强财政政策对雾霾治理的积极影响,充分发挥财政职能,建议完善财政资金的专项转移支付制度,推进资源税制改革,完善相关财政专项补贴政策,推进财政政策绩效评价. 展开更多
关键词 雾霾治理 财政政策 影响效应 T0PSIS模型
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The Impact of the Integration of Culture and Tourism Industry on the Upgrading of Tourism Industry Performance
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作者 BAI Yan 《Journal of Landscape Research》 2021年第5期93-99,102,共8页
Based on the provincial data of tourism and cultural industries from 2009 to 2019,this paper studies the impact of the integration of culture and tourism on the economic benefits of regional tourism in China.The resul... Based on the provincial data of tourism and cultural industries from 2009 to 2019,this paper studies the impact of the integration of culture and tourism on the economic benefits of regional tourism in China.The results show that:①The integration level of the two industries is generally low in all provinces and regions,and the regional differences are obvious.The integration degree of the central and eastern regions is generally higher than that of the western regions.②The integration degree of culture and tourism has a significant positive impact on the economic benefits of regional tourism.The influence on the central and eastern regions is greater than that on the western regions.③The level of informatization has a positive moderating effect on the economic benefits of regional tourism caused by the integration of culture and tourism.④Government intervention has a negative moderating effect on the economic benefits of tourism.In addition,the level of regional economic development,accessibility and tourism resource endowment are also significant factors affecting the economic benefits of regional tourism.The results show that promoting the deep integration of culture and tourism,promoting the informatization of tourism and moderate government intervention in the industry are conducive to improving the economic benefits of regional tourism. 展开更多
关键词 Integration of culture and tourism industry Upgrading of tourism industry performance Theoretical hypothesis impact effect
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体育饭圈形成机理、双边影响及规制路径
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作者 陈玉萍 《辽宁体育科技》 2025年第1期44-49,68,共7页
运用文献资料法和逻辑分析法,对体育饭圈形成机理、影响效应及其规制路径进行研究。研究认为:体育饭圈是由体育明星形象吸引力、粉丝情感或利益内驱力、体育资本牵引力、网络平台推动力等多因素融合作用形成的产物。体育饭圈对体育明星... 运用文献资料法和逻辑分析法,对体育饭圈形成机理、影响效应及其规制路径进行研究。研究认为:体育饭圈是由体育明星形象吸引力、粉丝情感或利益内驱力、体育资本牵引力、网络平台推动力等多因素融合作用形成的产物。体育饭圈对体育明星、粉丝、体育产业与体育事业皆有正向和负向的双边影响效应。从强化政府管控与加强法制建设、提升明星运动员素养、发挥粉丝社群领袖作用、引导饭圈参与公益服务与社会建设、讲好“大思政课”等路径着手,对体育饭圈进行有效规制治理,以维系中国体育发展的健康生态。 展开更多
关键词 体育饭圈 形成机理 影响效应 规制
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能源错配研究进展——特征事实、影响因素与效应评估
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作者 李跃 路开 吴步尘 《山东工商学院学报》 2025年第1期1-11,共11页
在“双碳”目标驱动下,能源错配问题引起了学界和政界广泛关注。利用VOSviewer可视化软件,基于中国知网和Web of Science核心合辑所收录的期刊文章,系统梳理了能源错配相关研究的发展脉络。发现研究重点集中于能源错配的特征事实分析、... 在“双碳”目标驱动下,能源错配问题引起了学界和政界广泛关注。利用VOSviewer可视化软件,基于中国知网和Web of Science核心合辑所收录的期刊文章,系统梳理了能源错配相关研究的发展脉络。发现研究重点集中于能源错配的特征事实分析、影响因素识别及影响效应评估等方面,能源错配测度方法主要有生产函数法、前沿技术分析法和影子价格测算法。研究认为,政府对能源价格的干预和供需失衡加剧了能源错配,技术能力的进步有助于缓解这一问题;能源错配对资源利用、经济发展和环境保护产生了负面影响,并具有显著的区域异质性。最后,研究指出了需要进一步补充完善的研究方向和领域,以期丰富相应研究成果,为我国能源优化配置的政策设计提供理论指导。 展开更多
关键词 能源错配 测度方法 影响因素 影响效应
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基于路面破损的车-钢桥面板裂纹扩展研究
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作者 汤胜 殷新锋 +1 位作者 张明 晏万里 《中外公路》 2025年第1期135-145,152,共12页
为研究不同路面破损情况下车辆对桥梁钢桥面板顶板焊趾裂纹扩展影响,该文建立悬索桥、精细化车辆及局部钢桥面板有限元模型,设置多组障碍物高度模拟路面破损,利用显式动力分析程序,实现车桥耦合振动模拟,提取不同车道、车速及障碍物高... 为研究不同路面破损情况下车辆对桥梁钢桥面板顶板焊趾裂纹扩展影响,该文建立悬索桥、精细化车辆及局部钢桥面板有限元模型,设置多组障碍物高度模拟路面破损,利用显式动力分析程序,实现车桥耦合振动模拟,提取不同车道、车速及障碍物高度下车辆对钢桥面板的作用力,并施加到局部钢桥面板模型获得顶板焊趾裂纹扩展寿命值。结果表明:①路面破损下车辆对桥梁的冲击效应会加快钢桥面板疲劳失效。行驶在正常路面不能使顶板焊趾裂纹扩展,而在路面破损下存在裂纹扩展寿命;②同一车道内顶板焊趾裂纹扩展寿命随行驶车速的增加而缩短,随障碍物高度的增加先减少后增加;③车道3中车辆车速80 km/h时,存在顶板焊趾裂纹扩展起始障碍物高度80 mm与最不利扩展障碍物高度100 mm,而在障碍物高度60 mm存在顶板焊趾裂纹扩展起始行驶车速90 km/h。 展开更多
关键词 车-桥耦合振动 冲击效应 钢桥面板 裂纹扩展 疲劳寿命
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系统性护理对输尿管镜碎石术患者的影响
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作者 刘玲燕 邱明霞 +3 位作者 许美泳 施惠雅 杨丹红 郑智慧 《护理实践与研究》 2025年第1期2-7,共6页
目的本研究旨在探讨系统性护理对输尿管镜碎石术患者的影响。方法选取2023年7月—2024年2月在医院接受输尿管镜碎石术治疗的160例患者作为研究对象,按照组间基线资料均衡可比的原则分为对照组和观察组,每组80例。对照组患者实施常规护理... 目的本研究旨在探讨系统性护理对输尿管镜碎石术患者的影响。方法选取2023年7月—2024年2月在医院接受输尿管镜碎石术治疗的160例患者作为研究对象,按照组间基线资料均衡可比的原则分为对照组和观察组,每组80例。对照组患者实施常规护理,观察组患者在对照组的基础上实施系统性护理,并分析两组患者的住院时间、腰痛症状消失时间、碎石完全排出时间、VAS评分、护理质量(心理干预、业务水平、护理态度、健康宣教)以及护理满意程度。结果观察组患者住院时间、腰痛症状消失时间、碎石完全排出时间均短于对照组,差异有统计学意义(P<0.05)。观察组患者干预后VAS评分低于对照组,差异有统计学意义(P<0.05);观察组患者护理质量(心理干预、业务水平、护理态度、健康宣教)评分均高于对照组,差异有统计学意义(P<0.05);观察组患者护理满意程度高于对照组,差异有统计学意义(P<0.05)。结论系统性护理在输尿管镜碎石术患者中不仅可以有效缓解疼痛、提高治疗效果,还能够提升护理质量和患者满意程度,有较好的护理效果。 展开更多
关键词 系统性护理 输尿管镜碎石术 腰痛 疼痛程度 护理质量 影响 住院时间 治疗效果
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