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Exploring the effect of a low-carbon city pilot policies on carbon dioxide emission intensity:Based on the PSM-DID method 被引量:2
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作者 Yan Song Xiulian Chen +2 位作者 Zhenran Li Zhiyuan Zeng Ming Zhang 《Chinese Journal of Population,Resources and Environment》 2022年第3期209-216,共8页
In 2010,the National Development and Reform Commission launched the low-carbon city(LCC)pilot pro‐gram.The scope of the pilot program was then gradually expanded to address the dilemma concerning eco‐nomic developme... In 2010,the National Development and Reform Commission launched the low-carbon city(LCC)pilot pro‐gram.The scope of the pilot program was then gradually expanded to address the dilemma concerning eco‐nomic development and low-carbon transition.Selecting the second batch of LCCs in China,this study uses a combination of propensity score matching and difference-in-differences models to determine the effect of LCC pilot policies on CO_(2) emission intensity.We also used the mediation effect model to further investigate its in‐ternal mechanism.The findings of the study are as follows.First,the LCC pilot policy plays an important role in reducing carbon emissions.Second,LCC pilots policies reduce CO_(2) emissions through intermediary paths of output adjustment and technological innovation.Third,our heterogeneity analysis reveals that cities with higher levels of economic growth and better levels of human capital have superior carbon emission reduction effects;lastly,non-resource-based cities have better carbon emission reduction effects. 展开更多
关键词 Low-carbon city(LCC) Carbon emissions psm-did Output adjustment Technology innovation
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区域大气污染协同治理能促进空气质量改善吗?--基于中国279个城市的PSM-DID实证研究 被引量:2
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作者 陆安颉 周建国 《长江流域资源与环境》 北大核心 2025年第3期652-667,共16页
当前我国复合型、跨域性空气污染问题日益突出,传统的属地治理模式再难应对,急需打破行政区划限制,推进区域大气污染协同治理。首先对大气污染协同治理政策的作用机理展开分析并提出研究假设;进一步基于2013~2020年我国279个地级及以上... 当前我国复合型、跨域性空气污染问题日益突出,传统的属地治理模式再难应对,急需打破行政区划限制,推进区域大气污染协同治理。首先对大气污染协同治理政策的作用机理展开分析并提出研究假设;进一步基于2013~2020年我国279个地级及以上城市的面板数据,运用双重差分倾向得分匹配法(PSM-DID),实证探究区域大气污染协同治理的政策效果和作用机制。研究发现:(1)基准回归分析结果表明,协同治理政策的实施显著降低了城市AQI指数和PM10、SO_(2)、NO_(2)、PM_(2.5)污染物的浓度,整体上促进了区域空气质量改善,一系列稳健性检验均表明结论的可靠性。(2)区域异质性分析结果表明,京津冀地区协同治理效果在促进空气质量改善和污染减排方面均显著优于长三角地区。(3)作用机制分析结果表明,区域大气污染协同治理主要通过促进产业结构升级、提升技术创新水平和加大污染源治理投资力度来改善区域空气质量,有效治理区域性、复合型大气污染问题。研究进一步提出政策建议。 展开更多
关键词 大气污染 区域协同治理 空气质量 psm-did
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人工智能技术对制造业就业的影响——基于PSM-DID模型
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作者 龙莹 赵浩然 《华南理工大学学报(社会科学版)》 2025年第3期61-73,共13页
基于2015—2023年的沪深A股上市制造业企业数据,依据是否融入人工智能产业链,将制造业企业划分为AI企业和非AI企业,通过多时点PSM-DID模型探究人工智能技术对我国制造业就业规模与就业结构的影响。研究发现,人工智能技术显著扩大了制造... 基于2015—2023年的沪深A股上市制造业企业数据,依据是否融入人工智能产业链,将制造业企业划分为AI企业和非AI企业,通过多时点PSM-DID模型探究人工智能技术对我国制造业就业规模与就业结构的影响。研究发现,人工智能技术显著扩大了制造业企业的整体就业规模,通过中介效应检验发现,人工智能技术主要通过提高企业研发投入强度来扩大企业的整体就业规模。进一步分析,人工智能技术的应用对研究生学历和高中及以下学历的员工有显著的正向效应,相比之下,大专学历的员工被人工智能技术的替代效应所挤出,出现“极化”现象。而且,人工智能技术对制造业就业规模的影响在不同部门、不同细分行业和不同地区中表现各异。在此基础上,提出政府和企业可通过政策引导、技术创新和教育培训,共同推动制造业可持续高质量发展,确保产业转型过程中就业市场的平稳过渡与繁荣。 展开更多
关键词 人工智能技术 制造业企业 就业规模 就业结构 psm-did模型
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高铁开通对中国航空网络结构特征的影响——基于PSM-DID模型的实证分析
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作者 景崇毅 郭韩一萌 高玉香 《交通运输研究》 2025年第2期54-64,共11页
为探究高铁网络扩张对中国航空网络结构的影响及其空间异质性特征,并为优化空铁竞合关系提供决策参考,采用PSM-DID模型,利用2000—2018年的高铁开通数据和航空网络数据,从航空网络的连通性、紧密性、易达性和中介性4个维度对高铁开通给... 为探究高铁网络扩张对中国航空网络结构的影响及其空间异质性特征,并为优化空铁竞合关系提供决策参考,采用PSM-DID模型,利用2000—2018年的高铁开通数据和航空网络数据,从航空网络的连通性、紧密性、易达性和中介性4个维度对高铁开通给航空网络结构特征带来的影响进行分析,并根据地区及机场规模差异等进行讨论。结果表明:①高铁开通对航空网络结构产生了显著的负面冲击;②地理位置、经济、环境等因素的差异导致冲击强度表现出“中部地区>东部地区>西部地区”的特征;③大型机场通过替代效应与互补效应的协同作用,能缓解高铁运营带来的客源分流压力,展现出较中小型机场更为突出的抗风险能力;④高铁开通拓展了机场群的市场辐射范围。基于此,提出如下政策建议:西部地区应优化短途航线布局;中小机场需发展低成本航空提升运营效率,大型机场应推进空铁联运整合;优先培育枢纽机场群,通过国际长航线开拓,提升网络韧性。 展开更多
关键词 交通运输 高速铁路 航空网络 网络结构 psm-did模型
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设立重点生态功能区对生态经济协调发展的影响研究--基于PSM-DID模型的实证分析
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作者 黄海燕 唐洁 《绿色科技》 2025年第1期223-228,共6页
重点生态功能区承担着重要的生态保障与生态产品供给功能,在接受中央财政转移支付的同时也实行严格的产业准入制度,因此对于设立重点生态功能区能否有效促进生态经济协调发展是值得关注的问题。本文将重点生态功能区的设立作为一项“准... 重点生态功能区承担着重要的生态保障与生态产品供给功能,在接受中央财政转移支付的同时也实行严格的产业准入制度,因此对于设立重点生态功能区能否有效促进生态经济协调发展是值得关注的问题。本文将重点生态功能区的设立作为一项“准自然实验”,基于2006-2022年贵州省72个县的面板数据,采用双重差分法(PSM-DID模型)评估重点生态功能区设立对贵州省72个县生态经济协调发展的影响。研究发现:重点生态功能区的设立能显著促进生态经济协调发展,机制分析结果表明重点生态功能区能通过产业结构升级效应、劳动力要素及资金要素的集聚效应促进生态经济协调发展。针对上述结论提出以下建议:①加快探索重点生态功能区生态产品价值实现路径,促进生态经济融合发展;②拓展重点生态功能区转移支付补偿方式并促进资金分配合理化。 展开更多
关键词 重点生态功能区 psm-did模型 生态经济协调发展 生态系统服务价值
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Study of the Transport Behavior of Multispherical Proppant in Intersecting Fracture Based on Discrete Element Method 被引量:1
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作者 Chengyong Peng JianshuWu +2 位作者 Mao Jiang Biao Yin Yishan Lou 《Energy Engineering》 EI 2025年第1期185-201,共17页
To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fract... To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on conductivity.Using reservoir production parameters and the discrete elementmethod,multispherical proppants were constructed.Additionally,a 3D fracture model,based on the specified conditions of the L block,employed coupled(Computational Fluid Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of multispherical proppants in intersecting fractures.Results indicate that turbulent kinetic energy is an intrinsic factor affecting proppant transport.Moreover,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture conductivity.Compared to small-angle fractures,controlling artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by controlling the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures. 展开更多
关键词 Hydraulic fracturing discrete element method PROPPANT SPHERICITY CFD-DEM
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政府引导基金对企业成长性的影响——基于PSM-DID的实证分析
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作者 杜佳凝 周霞 《商业会计》 2025年第4期111-114,共4页
政府引导基金是创投出资的主要力量,具有缓解市场失灵、推动科技创新繁荣的重要作用。文章选取创业板上市公司2017-2022年间的数据作为研究样本,在分析政府引导基金对企业成长性的影响时,采用了倾向得分匹配双重差分法(PSM-DID),研究发... 政府引导基金是创投出资的主要力量,具有缓解市场失灵、推动科技创新繁荣的重要作用。文章选取创业板上市公司2017-2022年间的数据作为研究样本,在分析政府引导基金对企业成长性的影响时,采用了倾向得分匹配双重差分法(PSM-DID),研究发现,政府引导基金对提升企业的成长性具有显著的正向影响;异质性分析发现,相对于非高新技术企业,政府引导基金的投入更有益于提高高新技术企业成长性。这一研究结论进一步丰富了企业成长性的影响因素,为上市公司发展转型、提升企业成长能力提供了一定参考和借鉴。国家应该积极设立政府引导基金,发挥政府引导基金的引导作用,吸引社会资本参与投资,优化政府引导基金的运作效率以及投资结构配置。 展开更多
关键词 政府引导基金 企业成长性 psm-did
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绿色信贷对商业银行风险承担能力的影响研究——基于PSM-DID模型实证分析
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作者 陶圆 李辉 丁勇 《华北金融》 2025年第1期1-14,共14页
加快实现绿色金融发展是贯彻落实新发展理念的战略要求。本文以2007—2022年81家商业银行微观数据为样本,采用PSM-DID模型和非线性回归模型分析银行绿色信贷与风险承担能力之间的关系,并进一步分析绿色信贷占比对银行风险承担能力的作... 加快实现绿色金融发展是贯彻落实新发展理念的战略要求。本文以2007—2022年81家商业银行微观数据为样本,采用PSM-DID模型和非线性回归模型分析银行绿色信贷与风险承担能力之间的关系,并进一步分析绿色信贷占比对银行风险承担能力的作用机制。研究表明:(1)实施绿色信贷政策和增加绿色信贷占比均能显著提升银行的风险承担能力。(2)银行绿色信贷占比与其风险承担能力呈“倒U”形关系。(3)从传导机制来看,绿色信贷提升银行风险承担水平的途径主要是风险转移效应和声誉效应,并且声誉效应对绿色信贷提高银行风险承担能力起正向的调节作用。 展开更多
关键词 绿色信贷 银行风险承担 psm-did 风险转移效应 声誉效应
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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage 被引量:1
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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In situ stress inversion using nonlinear stress boundaries achieved by the bubbling method 被引量:1
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作者 Xige Liu Chenchun Huang +3 位作者 Wancheng Zhu Joung Oh Chengguo Zhang Guangyao Si 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1510-1527,共18页
Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this cha... Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this challenge,nonlinear stress boundaries for a numerical model are determined through regression analysis of a series of nonlinear coefficient matrices,which are derived from the bubbling method.Considering the randomness and flexibility of the bubbling method,a parametric study is conducted to determine recommended ranges for these parameters,including the standard deviation(σb)of bubble radii,the non-uniform coefficient matrix number(λ)for nonlinear stress boundaries,and the number(m)and positions of in situ stress measurement points.A model case study provides a reference for the selection of these parameters.Additionally,when the nonlinear in situ stress inversion method is employed,stress distortion inevitably occurs near model boundaries,aligning with the Saint Venant's principle.Two strategies are proposed accordingly:employing a systematic reduction of nonlinear coefficients to achieve high inversion accuracy while minimizing significant stress distortion,and excluding regions with severe stress distortion near the model edges while utilizing the central part of the model for subsequent simulations.These two strategies have been successfully implemented in the nonlinear in situ stress inversion of the Xincheng Gold Mine and have achieved higher inversion accuracy than the linear method.Specifically,the linear and nonlinear inversion methods yield root mean square errors(RMSE)of 4.15 and 3.2,and inversion relative errors(δAve)of 22.08%and 17.55%,respectively.Therefore,the nonlinear inversion method outperforms the traditional multiple linear regression method,even in the presence of a systematic reduction in the nonlinear stress boundaries. 展开更多
关键词 In situ stress field Inversion method The bubbling method Nonlinear stress boundary Multiple linear regression method
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Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates
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作者 Yufeng Xing Ye Yuan Gen Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期329-355,共27页
The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytica... The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical shells.By taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue equations.Besides,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are investigated.It is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well. 展开更多
关键词 Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method
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Improved methods,properties,applications and prospects of microbial induced carbonate precipitation(MICP)treated soil:A review 被引量:2
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作者 Xuanshuo Zhang Hongyu Wang +3 位作者 Ya Wang Jinghui Wang Jing Cao Gang Zhang 《Biogeotechnics》 2025年第1期34-54,共21页
Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vi... Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications. 展开更多
关键词 Soil improvement Bio-cement MICP Improved methods Field application cases
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国土空间生态保护修复对中国脱贫地区经济发展的影响——基于PSM-DID方法的实证分析
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作者 张帅航 原野 +4 位作者 苗颖凤 曹辰瑜 赵嘉瑜 王霜 李倩 《干旱区地理》 北大核心 2025年第5期930-940,共11页
探究国土空间生态保护修复对中国脱贫地区经济发展的影响,可为脱贫地区经济可持续发展及后脱贫时代相对贫困地区乡村振兴工作提供科学依据。运用倾向得分匹配-双重差分(PSM-DID)模型,对我国“十三五”期间及“十四五”期间第一批、第二... 探究国土空间生态保护修复对中国脱贫地区经济发展的影响,可为脱贫地区经济可持续发展及后脱贫时代相对贫困地区乡村振兴工作提供科学依据。运用倾向得分匹配-双重差分(PSM-DID)模型,对我国“十三五”期间及“十四五”期间第一批、第二批国家级山水林田湖草沙一体化保护和修复工程项目(“山水工程”)共涉及的58个国家级脱贫县和与其自然社会经济本底条件类似的182个未列入国家“山水工程”的脱贫县的2010—2020年的经济面板数据进行对比,测度国土空间生态保护修复对中国脱贫地区经济发展的影响。结果表明:(1)在其他条件不变的情况下,相对于未实施国土空间生态保护修复的脱贫地区,实施国土空间生态保护修复的脱贫县经济发展速率显著提高了0.0329,这一结论在进行了平衡性检验、平行趋势检验及安慰剂检验等稳健性检验后仍成立。(2)国土空间生态保护修复实施中,宜考量工程实施带动经济发展的近远期效应。生态产品价值实现作为可持续推动脱贫地区经济发展重要手段,宜在完善相关生态产品价值实现制度的基础上,给脱贫地区更多政策支持,助力其实现“绿水青山”向“金山银山”转化。 展开更多
关键词 国土空间生态保护修复 脱贫地区 经济发展 psm-did
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一种基于Least Square Method算法的城轨车辆车门动作时间精准判断的研究
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作者 李宏菱 宋华杰 +3 位作者 马仲智 周辉 李晴 陈龙 《时代汽车》 2025年第3期190-192,共3页
为研究城市轨道交通车辆客室车门动作时间精准性,门的动作主要依靠直流无刷电机的驱动,所以门动作判断的根本,是对电机运动状态的判读,门运动过程中由于电机码盘线受杂波干扰,系统无法准确寻找计时点从而影响系统判断门运动时间;建立波... 为研究城市轨道交通车辆客室车门动作时间精准性,门的动作主要依靠直流无刷电机的驱动,所以门动作判断的根本,是对电机运动状态的判读,门运动过程中由于电机码盘线受杂波干扰,系统无法准确寻找计时点从而影响系统判断门运动时间;建立波形矫正模型,利用数学方法校准波形,让MCU找出最佳计时点并处理(误差不超过10ms),采用最小二乘法模型,通过最小化误差的平方和找到一组数据的最佳函数匹配,求得未知的数据,并使得这些求得的数据与实际数据之间误差的平方和为最小,可精准地得到门动作时间。模拟测试结果表明,门动作时间测算误差所示其误差为7.42ms,小于10ms。 展开更多
关键词 城轨车辆 客室车门 电机码盘 Least Square method算法 门动作时间精准
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Research on Bearing Fault Diagnosis Method Based on Deep Learning 被引量:1
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作者 Ting Zheng 《Journal of Electronic Research and Application》 2025年第1期1-6,共6页
Bearing is an indispensable key component in mechanical equipment,and its working state is directly related to the stability and safety of the whole equipment.In recent years,with the rapid development of artificial i... Bearing is an indispensable key component in mechanical equipment,and its working state is directly related to the stability and safety of the whole equipment.In recent years,with the rapid development of artificial intelligence technology,especially the breakthrough of deep learning technology,it provides a new idea for bearing fault diagnosis.Deep learning can automatically learn features from a large amount of data,has a strong nonlinear modeling ability,and can effectively solve the problems existing in traditional methods.Aiming at the key problems in bearing fault diagnosis,this paper studies the fault diagnosis method based on deep learning,which not only provides a new solution for bearing fault diagnosis but also provides a reference for the application of deep learning in other mechanical fault diagnosis fields. 展开更多
关键词 Deep learning Bearing failure Diagnostic methods
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A dual⁃parameter method for seismic resilience assessment of buildings 被引量:1
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作者 LI Shuang HU Binbin +1 位作者 LIU Wen ZHAI Changhai 《Journal of Southeast University(English Edition)》 2025年第1期1-11,共11页
To quantify the seismic resilience of buildings,a method for evaluating functional loss from the component level to the overall building is proposed,and the dual-parameter seismic resilience assessment method based on... To quantify the seismic resilience of buildings,a method for evaluating functional loss from the component level to the overall building is proposed,and the dual-parameter seismic resilience assessment method based on postearthquake loss and recovery time is improved.A threelevel function tree model is established,which can consider the dynamic changes in weight coefficients of different category of components relative to their functional losses.Bayesian networks are utilized to quantify the impact of weather conditions,construction technology levels,and worker skill levels on component repair time.A method for determining the real-time functional recovery curve of buildings based on the component repair process is proposed.Taking a three-story teaching building as an example,the seismic resilience indices under basic earthquakes and rare earthquakes are calculated.The results show that the seismic resilience grade of the teaching building is comprehensively judged as GradeⅢ,and its resilience grade is more significantly affected by postearthquake loss.The proposed method can be used to predict the seismic resilience of buildings prior to earthquakes,identify weak components within buildings,and provide guidance for taking measures to enhance the seismic resilience of buildings. 展开更多
关键词 seismic resilience assessment dual-parameter method functional loss recovery time Bayesian networks
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A Review of the Hydrodynamic Damping Characteristics of Blade-like Structures:Focus on the Quantitative Identification Methods and Key Influencing Parameters 被引量:1
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作者 Yongshun Zeng Zhaohui Qian +1 位作者 Jiayun Zhang Zhifeng Yao 《哈尔滨工程大学学报(英文版)》 2025年第1期21-34,共14页
Ocean energy has progressively gained considerable interest due to its sufficient potential to meet the world’s energy demand,and the blade is the core component in electricity generation from the ocean current.Howev... Ocean energy has progressively gained considerable interest due to its sufficient potential to meet the world’s energy demand,and the blade is the core component in electricity generation from the ocean current.However,the widened hydraulic excitation frequency may satisfy the blade resonance due to the time variation in the velocity and angle of attack of the ocean current,even resulting in blade fatigue and destructively interfering with grid stability.A key parameter that determines the resonance amplitude of the blade is the hydrodynamic damping ratio(HDR).However,HDR is difficult to obtain due to the complex fluid-structure interaction(FSI).Therefore,a literature review was conducted on the hydrodynamic damping characteristics of blade-like structures.The experimental and simulation methods used to identify and obtain the HDR quantitatively were described,placing emphasis on the experimental processes and simulation setups.Moreover,the accuracy and efficiency of different simulation methods were compared,and the modal work approach was recommended.The effects of key typical parameters,including flow velocity,angle of attack,gap,rotational speed,and cavitation,on the HDR were then summarized,and the suggestions on operating conditions were presented from the perspective of increasing the HDR.Subsequently,considering multiple flow parameters,several theoretical derivations and semi-empirical prediction formulas for HDR were introduced,and the accuracy and application were discussed.Based on the shortcomings of the existing research,the direction of future research was finally determined.The current work offers a clear understanding of the HDR of blade-like structures,which could improve the evaluation accuracy of flow-induced vibration in the design stage. 展开更多
关键词 Blade fatigue Hydrodynamic damping ratio Identification method Affecting factors Prediction formula
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Formation mechanism of herpetrione self-assembled nanoparticles based on p H-driven method 被引量:1
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作者 Yuwen Zhu Xiang Deng +4 位作者 Yan Wu Baode Shen Lingyu Hang Yuye Xue Hailong Yuan 《Chinese Chemical Letters》 2025年第1期387-391,共5页
The self-assembled nanoparticles(SAN)formed during the decoction process of traditional Chinese medicine(TCM)exhibit non-uniform particle sizes and a tendency for aggregation.Our group found that the p H-driven method... The self-assembled nanoparticles(SAN)formed during the decoction process of traditional Chinese medicine(TCM)exhibit non-uniform particle sizes and a tendency for aggregation.Our group found that the p H-driven method can improve the self-assembly phenomenon of Herpetospermum caudigerum Wall.,and the SAN exhibited uniform particle size and demonstrated good stability.In this paper,we analyzed the interactions between the main active compound,herpetrione(Her),and its main carrier,Herpetospermum caudigerum Wall.polysaccharide(HCWP),along with their self-assembly mechanisms under different p H values.The binding constants of Her and HCWP increase with rising p H,leading to the formation of Her-HCWP SAN with a smaller particle size,higher zeta potential,and improved thermal stability.While the contributions of hydrogen bonding and electrostatic attraction to the formation of Her-HCWP SAN increase with rising p H,the hydrophobic force consistently plays a dominant role.This study enhances our scientific understanding of the self-assembly phenomenon of TCM improved by p H driven method. 展开更多
关键词 Traditional Chinese medicine NANOPARTICLES Herpetrione Interaction pH-driven method Self-assembly Isothermal titration calorimetry
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Estimation of Chloride Diffusivity in Hydrated Tricalcium Silicate Using a Hydration-Diffusion Integrated Method
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作者 WANG Xin SHEN Dejian +2 位作者 TAO Sijie LIU Ruixin WU Shengxing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期49-64,共16页
This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydra... This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S paste.The results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age. 展开更多
关键词 tricalcium silicate simulation method chloride diffusion coefficient pore solution
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Optimal Scheduling of an Independent Electro-Hydrogen System with Hybrid Energy Storage Using a Multi-Objective Standardization Fusion Method
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作者 Suliang Ma Zeqing Meng +1 位作者 Mingxuan Chen Yuan Jiang 《Energy Engineering》 EI 2025年第1期63-84,共22页
In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is crucial.Still,it presents a challenge due to the significant deviations in values ofmultiple optimizatio... In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is crucial.Still,it presents a challenge due to the significant deviations in values ofmultiple optimization objective functions caused by their physical dimensions.These deviations seriously affect the scheduling process.A novel standardization fusion method has been established to address this issue by analyzing the variation process of each objective function’s values.The optimal scheduling results of IEHS with HESS indicate that the economy and overall energy loss can be improved 2–3 times under different optimization methods.The proposed method better balances all optimization objective functions and reduces the impact of their dimensionality.When the cost of BESS decreases by approximately 30%,its participation deepens by about 1 time.Moreover,if the price of the electrolyzer is less than 15¥/kWh or if the cost of the fuel cell drops below 4¥/kWh,their participation will increase substantially.This study aims to provide a more reasonable approach to solving multi-objective optimization problems. 展开更多
关键词 Electro-hydrogen system multi-objective optimization standardization method hybrid energy storage system
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