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基于代理模型和NSGA-Ⅱ的超高强钢电阻点焊工艺参数多目标优化

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焊接学报 2024年第4期45卷 20-25,I0004页

作者：卓文波谭国笔陈秋任侯泽宏王显会韩维建黄理南京理工大学机械工程学院南京210009 长三角先进材料研究院苏州215000 南京工业大学先进轻质高性能材料研究中心南京210009

为寻求超高强钢电阻点焊时最佳的焊接工艺参数,开展正交试验法设计三因素五水平的平板搭接点焊试验,以焊接时间、焊接电流和电极压力为可调的工艺参数,将熔核直径、压痕深度、拉剪强度及飞溅情况作为焊接接头质量评价指标.基于高斯过程... 详细信息

为寻求超高强钢电阻点焊时最佳的焊接工艺参数,开展正交试验法设计三因素五水平的平板搭接点焊试验,以焊接时间、焊接电流和电极压力为可调的工艺参数,将熔核直径、压痕深度、拉剪强度及飞溅情况作为焊接接头质量评价指标.基于高斯过程回归和BP神经网络建立起焊接工艺参数与焊接接头质量评价指标之间关系的代理模型,训练的结果显示模型精度很高.最后利用带精英策略的非支配排序的遗传算法NSGA-Ⅱ实现多目标优化,得到各评价指标之间的最优pareto解集.经验证,各评价模型的相对误差值都很小.结果表明,该优化方法有较好的预测效果和稳定性.通过使用较少的试验数据,建立优化模型的方法对电阻点焊及其它焊接领域最佳焊接工艺参数的选取具有重要的指导价值.

关键词：多目标优化电阻点焊工艺参数代理模型非支配排序遗传算法

Synthesis and Thermal Behavior of New Precursors for B-C-N Ceramics

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Journal of Materials Science & Technology 2010年第3期26卷 228-233页

作者： Shaohua Dong weijian han Yongming Luo Tong Zhao Caihong Xu Institute of Chemistry Chinese Academy of Sciences Beijing 100190China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Three new borazine derivatives,2,4,6-tri（allylamino）borazine （CH 2 =CHCH 2 NHBNH） 3 （1）,2,4,6-tri（3ethynylanilino）borazine （CH≡CC 6 H 4 NHBNH） 3 （2）,and 2,4,6-tri（4-propargyl oxyanilino）borazine （CH≡ CCH 2 OC 6 H 4 NHBNH） 3 （3） were synthesized by reaction of 2,4,6-trichloro-borazine Cl 3 B 3 N 3 H 3 （TCB） with corresponding primary amines,*** thermal behavior was studied by differential scanning calorimetry （DSC） and thermogravimetric analysis （TGA）.These molecules were easily crosslinked via thermal polymerization of reactive ethynyl or vinyl *** pyrolytic residues of borazines were investigated by X-ray photoelectron spectroscopy （XPS）,powder X-ray diffraction （XRD）,and scanning electron microscopy （SEM）.The analytic results indicated that B-C-N ceramics were formed upon pyrolysis of the borazines under an inert atmosphere.

关键词： Precursors Thermal properties B-C-N ceramic

Life cycle analysis and choice of natural gas-based automotive alternative fuels in Chongqing Municipality, China

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Frontiers of Environmental Science & Engineering 2007年第3期1卷 292-298页

作者： WU Rui LI Guangyi ZhanG Zongyi REN Yulong han weijian Chongqing University Chongqing 400044China Ford Motor Company Dearborn MI 48150USA

Road transport produces significant amounts of emissions by using crude oil as the primary energy source.A reduction of emissions can be achieved by implementing alternative fuel *** objective of this study is to carry out an economic,environmental and energy(EEE)life cycle study on natural gas-based automotive fuels with conven-tional gasoline in an abundant region of China.A set of indices of four fuels/vehicle systems on the basis of life cycle are assessed in terms of impact of EEE,in which natural gas produces compressed natural gas(CNG),methanol,dimethy-lether(DME)and Fischer Tropsch diesel(FTD).The study included fuel production,vehicle production,vehicle opera-tion,infrastructure and vehicle end of life as a system for each fuel/vehicle system.A generic gasoline fueled car is used as a *** have been reviewed and modified based on the best knowledge available to Chongqing local *** indicated that when we could not change electric and hydrogen fuel cell vehicles into commercial vehicles on a large scale,direct use of CNG in a dedicated or bi-fuel vehicle is an eco-nomical choice for the region which is most energy efficient and more environmental *** study can be used to support decisions on how natural gas resources can best be utilized as a fuel/energy resource for automobiles,and what issues need to be resolved in *** models and approaches for this study can be applied to other regions of China as long as all the assumptions are well defined and modified to find a substitute automotive energy source and establish an energy policy in a specific region.

关键词： life cycle assessment natural gas based substitute automotive fuels

Attribution of PM_(2.5) exposure in Beijing-Tianjin-Hebei region to emissions:implication to control strategies

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Science Bulletin 2017年第13期62卷 957-964页

作者： Xin Li Qiang Zhang Yang Zhang Lin Zhang Yuxuan Wang Qianqian Zhang Meng Li Yixuan Zheng Guannan Geng Timothy J.Wallington weijian han Wei Shen Kebin He Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua University Department of Marine Earthand Atmospheric SciencesNorth Carolina State University Collaborative Innovation Center for Regional Environmental Quality Laboratory for Climate and Ocean-Atmosphere Sciences Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking University Department of Marine Sciences Texas A&M University at Galveston Department of Atmospheric Sciences Texas A&M UniversityCollege Station National Satellite Meteorological Center China Meteorological Administration Research and Advanced Engineering Ford Motor Company Asia Pacific Research Ford Motor Company State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua University

The Beijing-Tianjin-Hebei （BTH） region is one of the most heavily polluted regions in China, with both high PM2.5 concentrations and a high population density. A quantitative source-receptor relationship can provide valuable insights that can inform effective emission control strategies. Both source appor- tionment （SA） and source sensitivity （SS） can provide such information from different perspectives. In this study, both methods are applied in northern China to identify the most significant emission cate- gories and source regions for PMz5 exposure in BTH in 2013. Despite their differences, both models show similar distribution patterns for population and simulated PM2.5 concentrations, resulting in overall high PM2.5 exposure values （approximately 110 Ixg/m3） and particularly high exposure values during the win- ter （approximately 200 ktg/m3）. Both methods show that local emissions play a dominant role （70%）, with some contribution from surrounding provinces （e.g., Shandong） via regional transport. The two methods also agree on the priority of local emission controls： both identify industrial, residential, and agricultural emissions as the top three categories that should be controlled locally. In addition, the effect of control- ling agricultural ammonia emissions is approximately doubled when the co-benefits of reducing nitrate are considered. The synthesis of SA and SS for addressing specific categories of emissions provides a quantitative basis for the development of emission control strategies and policies for controlling PM2.5 in China.

关键词： PM2.5 exposureSource apportionmentSource sensitivityControl priorityChina

车用合成燃料能源消费和温室气体排放对比分析

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清华大学学报（自然科学版） 2007年第3期47卷 441-444页

作者：申威张阿玲韩维建清华大学公共管理学院北京100084 清华大学核能与新能源技术研究院北京100084 福特汽车(中国)有限公司北京100004

为了评价在我国发展以天然气和煤为原料的车用合成燃料所带来的能源和全球变暖影响,使用“从矿井到车轮”的方法对甲醇、二甲醚和费托柴油在资源开采、炼制加工、运输分配及最终使用中的能耗和温室气体排放进行定量计算,并与传统汽油和... 详细信息

为了评价在我国发展以天然气和煤为原料的车用合成燃料所带来的能源和全球变暖影响,使用“从矿井到车轮”的方法对甲醇、二甲醚和费托柴油在资源开采、炼制加工、运输分配及最终使用中的能耗和温室气体排放进行定量计算,并与传统汽油和柴油的相关指标进行对比。计算结果表明,甲醇、二甲醚和费托柴油的全周期石油消耗远低于汽油和柴油,对解决中国石油安全问题有一定作用。在能源消费总量、化石能源消费量和温室气体排放量方面,天然气基燃料优于煤基燃料,但两者均明显劣于汽柴油,对中国未来承担温室气体减排责任构成潜在压力。

关键词：温室气体天然气煤合成燃料甲醇二甲醚费托柴油

变频+移相控制的双有源串联谐振DC-DC变换器的小信号建模

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西北工业大学学报 2019年第4期37卷 830-837页

作者：韩伟健马瑞卿刘青西北工业大学自动化学院陕西西安710072 帕多瓦大学信息工程学院意大利帕多瓦35131

变频+移相双自由度控制技术能够实现双有源串联谐振DC-DC变换器在宽范围工况下的零电压开通,从而有效提升变换器的工作效率和可靠性。提出了变频+移相控制下双有源串联谐振DC-DC变换器的小信号连续域模型,为研究在该控制机制下变换器的... 详细信息

变频+移相双自由度控制技术能够实现双有源串联谐振DC-DC变换器在宽范围工况下的零电压开通,从而有效提升变换器的工作效率和可靠性。提出了变频+移相控制下双有源串联谐振DC-DC变换器的小信号连续域模型,为研究在该控制机制下变换器的动态特性和闭环控制器的设计提供依据。所建立的模型基于广义平均建模法,选取输出电压的直流分量和电感电流、谐振电容电压的基波分量作为状态变量,准确描述了谐振腔对变换器动态特性的影响。在此基础上设计了输出电压闭环调节器,实现了变换器在ZVS变频+移相控制下的稳定运行。理论分析通过Matlab/PLECS仿真和1台800 W原理样机进行了验证。

关键词： DC-DC变换器双有源串联谐振小信号建模变频移相

车用替代燃料能源消费和温室气体排放对比研究

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天然气工业 2006年第11期26卷 148-152页

作者：申威张阿玲韩为建清华大学公共管理学院清华大学核能与新能源技术研究院美国福特汽车公司

为了定量解释以天然气为原料的不同车用替代燃料的节能和温室气体减排潜力,使用国际流行的Well-to-Wheel研究方法,依靠来自石油天然气开采、处理和加工工业的大量一线数据,对中国目前正在使用和拟议开发的4种来自天然气的车用燃料与传... 详细信息

为了定量解释以天然气为原料的不同车用替代燃料的节能和温室气体减排潜力,使用国际流行的Well-to-Wheel研究方法,依靠来自石油天然气开采、处理和加工工业的大量一线数据,对中国目前正在使用和拟议开发的4种来自天然气的车用燃料与传统汽柴油燃料进行了对比研究。从全生命周期的角度来看,天然气制备的液体燃料——甲醇、二甲醚和天然气合成油在能源消耗量和温室气体排放量方面明显高于汽柴油,压缩天然气是唯一可以在上述两个方面与传统燃料竞争的天然气基车用燃料。天然气基车用燃料的一个优势是全生命周期的石油消耗远低于汽柴油,对短期石油安全问题有一定缓解作用。在目前技术水平下,在我国大规模推广以天然气为原料的合成液体燃料应该慎重。如果从节能和温室气体减排的角度来看,发展混合动力车,提高车辆的燃料经济性水平,则是更有吸引力的选择。

关键词：天然气甲醇二甲醚天然气合成油汽车替代燃料温室气体能源消耗对比

A Joint Dynamic Estimation Algorithm of Vehicle Mass and Road Slope Considering Braking and Turning

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A Joint Dynamic Estimation Algorithm of Vehicle Mass and Roa...

第30届中国控制与决策会议

作者： Min Zhao Fan Yang Dihua Sun weijian han Fei Xie Tao Chen Key Laboratory of Dependable Service Computing in Cyber Physical Society of Ministry of Education College of Automation Chongqing University Ford Motor Company China Automotive Engineering Research Institute Co. Ltd

Accurate estimation of vehicle mass and road slope is of great significance to the vehicle’s intelligent control and realizing smart and green *** the strong coupling between vehicle mass and road slope in vehicle dynamic model and the effect of braking and turning during actual driving, this paper presents a dynamic joint estimation method of vehicle mass and road slope considering the effect of braking and turning based on the vehicle longitudinal dynamics ***, the road slope of the current step is estimated based on the EKF. Then, based on the estimated road slope, the vehicle mass is estimated through the RLS method with forgetting factor. And the method of nested loop is used to decouple the road slope and vehicle mass estimation to realize the dynamic estimation of the two ***, the effects of braking and turning during driving are eliminated by means of state keeping and segment *** experimental results show that the proposed joint dynamic estimation method of vehicle mass and road slope has good robustness, fast convergence rate and high accuracy.

关键词： Vehicle mass Road slope Joint estimation Braking and turning EKF RLS

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碳中和目标驱动下生物质燃料技术研究进展

化工进展 2024年第5期43卷 2463-2474页

作者：韩伟韩恒文程薇汤玮健中石化石油化工科学研究院有限公司北京100083

在碳中和目标的驱动下,炼化企业必须寻找新的路径,大力开发低碳、零碳的炼化新技术。生物基燃料性能与石油基燃料相近,但其全生命周期碳排放大幅降低,以生物质为原料生产替代燃料的技术,正成为炼油厂实现低碳、零碳发展的重要手段之一... 详细信息

在碳中和目标的驱动下,炼化企业必须寻找新的路径,大力开发低碳、零碳的炼化新技术。生物基燃料性能与石油基燃料相近,但其全生命周期碳排放大幅降低,以生物质为原料生产替代燃料的技术,正成为炼油厂实现低碳、零碳发展的重要手段之一。本文综述了由生物质原料制碳氢类燃料(b-Fuels)相关技术的研究进展和发展趋势,主要包括无甘油生成的酯交换技术,控制产物选择性的酯交换技术,生物质油热裂解、催化裂解、加氢裂化技术,以及生物质与石油馏分共炼技术等,同时对未来炼化企业实现碳中和的技术发展路径进行了探讨,以期为炼厂转型发展提供思路借鉴。

关键词：碳中和生物质合成燃料酯交换加氢裂化共炼 CO_(2)利用