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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 98-107页

作者： Li Hongzhen Li Shengbin feng zhuangzhuang Jiang Mengmeng Li Ning Dong Fuqiang Shandong Yimeng Traffic Development Group Co. Ltd.Zibo 276004China College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China

In this study,the regenerative effects of different regenerants on aged SBS-modified asphalt from different perspectives were investigated,including their conventional properties,viscoelastic behavior,creep-related properties,and *** oils composed of different proportions of aromatic and saturated hydrocarbons as well as the styrene-butadiene-styrene(SBS)restorer were used to prepare the *** results showed that the components of the base oil of the regenerant played a crucial role in determining the characteristics and performance of the recycled SBSmodified *** containing a high proportion of aromatics dissolved the hard segment in the SBS restorer,thereby delaying the effect of a reduction in the regenerants on the performance of the aged asphalts at a high *** containing a high proportion of saturates dissolved the soft segment in the SBS restorer to enhance the lowtemperature performance of the recycled *** addition,the stress sensitivity of the recycled asphalts increased with the fraction of aromatics in the *** the aromatic content of the base oil components of the regenerants increased and their saturate content decreased,the state of dispersion of the SBS phase in the recycled SBS-modified asphalts *** optimal content of aromatics in the base oil of the regenerants should be set in the range of 33%to 47%to ensure the adequate performance of the recycled asphalts and a high efficiency of the SBS restorer.

关键词： aged SBS-modified asphalt regeneration mechanisms base oil rheological properties morphology

三相PWM整流器离散空间矢量无模型预测电流控制策略

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电机与控制学报 2024年第6期28卷 163-170页

作者：胡存刚尹政张悦罗魁芮涛冯壮壮中国电力科学研究院有限公司新能源与储能运行控制国家重点实验室北京100192 安徽大学电气工程与自动化学院安徽合肥230601 安徽大学互联网学院安徽合肥230601

针对PWM整流器模型预测控制对系数参数准确性高度依赖的问题,提出一种基于离散空间矢量的无模型预测电流控制(MFPCC)策略。该策略通过矢量合成,在每个控制周期应用两个基本矢量,提高了预测电流的准确性;通过峰谷采样,分别测量并存储上... 详细信息

针对PWM整流器模型预测控制对系数参数准确性高度依赖的问题,提出一种基于离散空间矢量的无模型预测电流控制(MFPCC)策略。该策略通过矢量合成,在每个控制周期应用两个基本矢量,提高了预测电流的准确性;通过峰谷采样,分别测量并存储上一控制周期两个基本矢量作用下的电流梯度;并建立电流梯度方程,从而根据应用矢量的电流梯度进一步更新剩余6个未应用矢量的电流梯度,结合当前时刻的电流采样值,实现未来时刻的电流预测,得到下一时刻最优的虚拟矢量。该方法不依赖于任何系统参数,且消除了传统MFPCC策略中电流梯度更新停滞现象,降低了输出电流谐波。最后,通过实验和仿真验证了所提方法的有效性和优越性。

关键词： PWM整流器无模型预测电流控制离散空间矢量电流梯度更新停滞现象

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基于云-TOPSIS-灰关联分析模型的产品服务系统方案评价技术

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现代制造工程 2024年第2期 38-44页

作者：吕锋张淑萍刘芬冯壮壮高鸣河南科技大学机电工程学院洛阳471003 第一拖拉机股份有限公司制造工程中心洛阳471003

方案评价是产品服务系统设计的关键环节之一,评价结果的合理性对企业发展至关重要。基于最小平方和法,构建了云-TOPSIS-灰关联分析模型,对产品服务系统方案进行评价。引入云模型和相对偏好关系量化离散型指标,解决专家评价的模糊性和随... 详细信息

方案评价是产品服务系统设计的关键环节之一,评价结果的合理性对企业发展至关重要。基于最小平方和法,构建了云-TOPSIS-灰关联分析模型,对产品服务系统方案进行评价。引入云模型和相对偏好关系量化离散型指标,解决专家评价的模糊性和随机性问题。运用TOPSIS灰关联分析法确定正、负理想灰关联系数矩阵,集成指标权重和正、负理想灰关联系数矩阵建立正、负理想加权灰关联系数矩阵,兼顾了几何方案序列曲线的位置接近度和形状相似度。运用最小平方和法求解灰关联投影系数,确定方案排序。以某农业装备企业拖拉机产品服务系统方案评价为实例,验证了所提模型的科学性和可行性。

关键词：产品服务系统方案评价云模型 TOPSIS灰关联分析

产品服务系统设计中顾客需求重要度确定方法研究

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制造技术与机床 2024年第4期 173-180页

作者：吕锋刘芬冯壮壮张淑萍赵梓渌吕玲河南科技大学机电工程学院河南洛阳471003 机械装备先进制造河南省协同创新中心河南洛阳471003 河南省商丘市梁园区公路事业发展中心河南商丘476099

为了准确地反映产品服务系统设计中的顾客需求,文章基于手段-目的链理论从顾客期望角度获取顾客需求,提出了云模型、模糊DEMATEL和改进的分析型Kano模型相结合的方法确定顾客需求重要度。利用云模型解决专家评价模糊不确定问题,确定顾... 详细信息

为了准确地反映产品服务系统设计中的顾客需求,文章基于手段-目的链理论从顾客期望角度获取顾客需求,提出了云模型、模糊DEMATEL和改进的分析型Kano模型相结合的方法确定顾客需求重要度。利用云模型解决专家评价模糊不确定问题,确定顾客需求初始重要度。考虑到顾客需求间的有向影响关系,引入模糊DEMATEL方法,对顾客需求初始重要度进行修正。基于贴近度的顾客需求分类准则,构建了改进的分析型Kano模型,引入基于顾客满意度的顾客需求重要度指数和满意度指数,确定顾客需求最终重要度。以某数控机床产品服务系统设计为例,验证了所提模型的可行性和有效性。

关键词：产品服务系统顾客需求云模型模糊DEMATEL 分析型Kano模型

秸秆和氮肥耦合管控对盐渍化土壤地力综合效应的影响

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农业环境科学学报 2024年第8期43卷 1771-1785页

作者：牟云芳史海滨闫建文祁茜冯壮壮胡智远苏永德内蒙古农业大学水利与土木建筑工程学院呼和浩特010018 高效节水技术装备与水土环境效应内蒙古自治区工程研究中心呼和浩特010018

为研究河套灌区盐渍化土壤秸秆配施氮肥模式下土壤水盐迁移特征规律,明晰该模式下地力提升综合评价效应,通过田间试验,设置3种秸秆还田量[无秸秆还田(C0)、4500 kg·hm^(-2)( C1)、9000 kg·hm^(-2)( C2)]和3种施肥水平[不施氮(N0)、传... 详细信息

为研究河套灌区盐渍化土壤秸秆配施氮肥模式下土壤水盐迁移特征规律,明晰该模式下地力提升综合评价效应,通过田间试验,设置3种秸秆还田量[无秸秆还田(C0)、4500 kg·hm^(-2)( C1)、9000 kg·hm^(-2)( C2)]和3种施肥水平[不施氮(N0)、传统施氮量减氮30%即210 kg·hm^(-2)( N1)、300 kg·hm^(-2)( N2)]。结果表明:灌水后秸秆隔层形成了“蓄水层”和“隔盐层”,秸秆隔层及上层土壤储水量较无秸秆还田显著提高22.19%、脱盐率提高18.20%,在秸秆下层土壤呈现不同程度积盐,耕层土壤盐分始终随秸秆还田量的增加而降低,C2处理脱盐效果最好。秸秆腐解呈指数衰减趋势增长,秸秆腐解速率前60 d快,后90 d逐渐减缓。秸秆还田量和施氮量均对秸秆腐解有显著影响,C2N2处理秸秆累计腐解率为67.02%,较C2N0处理提高29.57%,配施氮肥可刺激秸秆中有机物分解和营养物质释放。单施氮肥严重降低了土壤有机质和养分的供应,同时添加秸秆明显降低了土壤无机氮的残留量。秸秆还田与氮肥的互作对玉米产量有极显著影响,C2处理玉米产量随施氮量的增加呈先增后减趋势。氮素过多会抑制秸秆腐解,降低土壤中养分的积累,从而影响作物生长,C2N1处理的产量最高为16985 kg·hm^(-2),较当地常规施肥C0N2处理提高9.47%。综合考虑土壤结构、水盐运移、养分释放及作物产量,采用熵值法建立综合评价回归模型,结果表明玉米秸秆还田量9000 kg·hm^(-2)配施氮肥210 kg·hm^(-2)为最佳模式。

关键词：秸秆还田施氮量秸秆腐解土壤水盐分布玉米产量

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并网逆变器最优开关序列模型预测电流控制

电机与控制学报 2024年第8期28卷 135-142页

作者：胡存刚孙晓磊张悦芮涛尹政冯壮壮王尧安徽大学电气工程与自动化学院安徽合肥230601 中国电力科学研究院有限公司新能源与储能运行控制国家重点实验室北京100192 安徽大学互联网学院安徽合肥230601

传统的并网逆变器模型预测电流控制方法仅在控制周期内对电流波形进行单点预测,忽略了逆变器开关状态变化引起的输出电流纹波,为此提出一种改进的最优开关序列并网逆变器模型预测电流控制策略。首先,为减小开关切换次数、优化频谱分布,... 详细信息

传统的并网逆变器模型预测电流控制方法仅在控制周期内对电流波形进行单点预测,忽略了逆变器开关状态变化引起的输出电流纹波,为此提出一种改进的最优开关序列并网逆变器模型预测电流控制策略。首先,为减小开关切换次数、优化频谱分布,对空间电压矢量组合进行重新排列,设计6组开关序列,并根据开关序列提出基于无差拍的矢量持续时间计算方法。其次,在一个控制周期内设置8个电流预测点,以计算开关序列在控制周期内作用所产生的电流预测误差,并通过累加电流预测误差构造预测控制的价值函数,选择使价值函数最低的开关序列作为最优序列组合,提高并网电流波形质量。最后,通过实验验证所提策略在降低并网逆变器输出电流纹波方面的有效性。

关键词：并网逆变器模型预测电流控制最优开关序列无差拍控制优化价值函数

Reversion of natural ageing and restoration of quick bake-hardening response in Al-Zn-Mg-Cu alloy

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Journal of Materials Science & Technology 2021年第36期95卷 88-94页

作者： Chunhui Liu zhuangzhuang feng Peipei Ma Yihui Zhou Guohui Li Lihua Zhan Light Alloy Research Institute of Central South University State Key Laboratory of High-Performance Complex ManufacturingChangsha 410083China School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China

The high-strength Al-Zn-Mg-Cu alloy provides much better dent resistance and weight-reduction potential compared to the conventional Al alloys used for the automobile body ***,natural ageing(NA)significantly reduces the formability of Al-Zn-Mg-Cu *** reversion of natural ageing has been systematically investigated by hardness test,tensile test,differential scanning calorimetry(DSC)and transmission electron microscopy(TEM).Substantial reversion of natural ageing and thus hardness decrease occurs immediately upon thermal treatment at 120–210℃in an Al-Zn-Mg-Cu *** the hardness of the most reverted state decreases with increasing temperature,the lowest hardness is still higher than the as-quenched state by 30 *** revealed by the complementary DSC and TEM observations,this is ascribed to the synchronization of the dissolution and the re-precipitation of the solutes in the NA clusters during reversion *** at 180–210℃for less than 30 s leads to a hardness decline of 40 *** hardening kinetics during NA after reversion is slower than that during first-time NA due to the reduced vacancy *** ageing at 180℃for 30 min after secondary NA of less than 24 h induces intensive precipitation of plate-like pre-ηphases and a giant strength increase of 188–204 *** use of high strength Al-Zn-Mg-Cu alloy in automobile body panels could be realized by appropriate reversion treatment improving the formability and the quick bake hardening response.

关键词： Reversion Natural ageing Bake-hardening response Vacancy Al-Zn-Mg-Cu alloy

A Cloud Framework for High Spatial Resolution Soil Moisture Mapping from Radar and Optical Satellite Imageries

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Chinese Geographical Science 2023年第4期33卷 649-663页

作者： GUO Tianhao ZHENG Jia WANG Chunmei TAO Zui ZHENG Xingming WANG Qi LI Lei feng zhuangzhuang WANG Xigang LI Xinbiao KE Liwei Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Changchun Jingyuetan Remote Sensing Test Site Changchun 130102China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China China Centre for Resources Satellite Data and Application China Aerospace Science and Technology CorporationBeijing 100094China College of Geoexploration Science and Technology Jilin UniversityChangchun 130026China School of Geomatics and Prospecting Engineering Jilin Jianzhu UniversityChangchun 130118China

Soil moisture plays an important role in crop yield estimation,irrigation management,*** sensing technology has potential for large-scale and high spatial soil moisture ***,offline remote sensing data processing is time-consuming and resource-intensive,and significantly hampers the efficiency and timeliness of soil moisture *** to the high-speed computing capabilities of remote sensing cloud platforms,a High Spatial Resolution Soil Moisture Estimation Framework(HSRSMEF)based on the Google Earth Engine(GEE)platform was developed in this *** functions of the HSRSMEF include research area and input datasets customization,radar speckle noise filtering,optical-radar image spatio-temporal matching,soil moisture retrieving,soil moisture visualization and *** paper tested the performance of HSRSMEF by combining Sentinel-1,Sentinel-2 images and insitu soil moisture data in the central farmland area of Jilin Province,*** Normalized Difference Vegetation Index(NDVI)based on the Savitzky-Golay algorithm conforms to the crop growth cycle,and its correlation with the original NDVI is about 0.99(P<0.001).The soil moisture accuracy of the random forest model(R 2=0.942,RMSE=0.013 m3/m3)is better than that of the water cloud model(R 2=0.334,RMSE=0.091 m3/m3).HSRSMEF transfers time-consuming offline operations to cloud computing platforms,achieving rapid and simplified high spatial resolution soil moisture mapping.

关键词： soil moisture(SM) Google Earth Engine(GEE) Cloud Computing Platform High Spatial Resolution Soil Moisture Estimation Framework(HSRSMEF) remote sensing Sentienl-1 Sentinel-2 Northeast China

Covalent organic frameworks/carbon nanotubes composite with cobalt(II)pyrimidine sites for bifunctional oxygen electrocatalysis

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Nano Materials Science 2024年第4期6卷 419-427页

作者： zhuangzhuang Wu Lijuan feng Zhe Lu Xinxin Yu Yuzhen Zhao Junming Luo Shaolei Wang Xinlong Tian Qi Chen State Key Laboratory of Marine Resource Utilization in South China Sea School of Marine Science and Engineering Hainan University Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education School of Chemistry Northeast Normal University School of Bioengineering Zhuhai Campus of Zunyi Medical University

With characteristics and advantages of functional composite materials, they are commendably adopted in numerous fields especially in oxygen electrocatalysis, which is due to the significant synergies between various components. Herein, a novel bifunctional oxygen electrocatalyst（Co-CNT@COF-Pyr） has been synthesized through in-situ growth of covalent organic frameworks（COFs） layers on the outer surface of highly conductive carbon nanotubes（CNTs） followed by coordination with Co（II）. For electrocatalytic OER, Co-CNT@COF-Pyr reveals a low overpotential（438 mV） in alkaline electrolyte（1.0 M aqueous solution of KOH） with a current density of 10 mA cm-2, which is comparable to most discovered COF-based catalysts. For electrocatalytic ORR, CoCNT@COF-Pyr exhibits a low H2O2yield range（9.0 %–10.1 %） and a reaction pathway close to 4e-（n =3.82–3.80） in alkaline electrolyte（0.1 M aqueous solution of KOH） within the test potential range of 0.1–0.6 V ***, which is superior to most reported COF-based catalysts. Hence, this research could not only offer an innovative insight into the construction of composites, but also facilitate the practical application of renewable fuel cells, closed water cycle, and rechargeable metal-air batteries.

关键词： Oxygen electrocatalysis Covalent organic frameworks Carbon nanotubes Composite materials

Bird’s-eye view of recycled solid wastes in road engineering

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Journal of Road Engineering 2024年第2期4卷 93-150页

作者： zhuangzhuang Liu Tengteng feng Xingyi Zhu Jie Gao Kui Hu Meng Guo Fan Gu feng Li School of Highway Chang'an UniversityXi'an 710064China Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an UniversityXi'an 710064China Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang 330013China College of Civil Engineering and Architecture Henan University of TechnologyZhengzhou 450001China State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China School of Traffic&Transportation Engineering Changsha University of Science and TechnologyChangsha 410114China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China

Recent trends in road engineering have explored the potential of incorporating recycled solid wastes into infrastructures that including pavements,bridges,tunnels,and accessory *** utilization of solid wastes is expected to offer sustainable solutions to waste recycling while enhancing the performance of *** review provides an extensive analysis of the recycling of three main types of solid wastes for road engineering purposes:industrial solid waste,infrastructure solid waste,and municipal life solid *** solid wastes suitable for road engineering generally include coal gangue,fly ash,blast furnace slag,silica fume,and steel slag,*** solid wastes recycled in road engineering primarily consist of construction&demolition waste,reclaimed asphalt pavements,and recycled cement ***,recent exploration has extended to the utilization of municipal life solid wastes,such as incinerated bottom ash,glass waste,electronics waste,plastic waste,and rubber waste in road engineering *** recycled solid wastes are categorized into solid waste aggregates,solid waste cements,and solid waste fillers,each playing distinct roles in road *** of solid waste acting aggregates,cements,and fillers in road infrastructures were fully investigated,including their pozzolanic properties,integration effects to virgin materials,modification or enhancement solutions,engineering *** of these materials not only addresses the challenge of waste management but also offers environmental benefits aiming carbon neutral and contributes to sustainable infrastructure ***,challenges such as variability in material properties,environmental impact mitigation,secondary pollution to environment by leaching,and concerns regarding long-term performance need to be further *** these challenges,the recycled solid wastes hold immense potential in revolutionizing road construction

关键词： Road engineering Industrial solid waste Infrastructure solid waste Municipal life waste Recycled materials