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Optimal Predictive Control for Path Following of a Full Drive-by-Wire Vehicle at Varying Speeds

Chinese Journal of Mechanical Engineering 2017年第3期30卷 711-721页

作者： Pan song Bolin GAO Shugang XIE rui FANG china automotive technology and research center Tianjin 300300China

The current research of the global chassis control problem for the full drive-by-wire vehicle focuses on the control allocation （CA） of the four-wheel-distributed trac- tion/braking/steering systems. However, the path following performance and the handling stability of the vehicle can be enhanced a step further by automatically adjusting the vehicle speed to the optimal value. The optimal solution for the combined longitudinal and lateral motion control （MC） problem is given. First, a new variable step-size spatial transformation method is proposed and utilized in the prediction model to derive the dynamics of the vehicle with respect to the road, such that the tracking errors can be explicitly obtained over the prediction horizon at varying speeds. Second, a nonlinear model predictive con- trol （NMPC） algorithm is introduced to handle the non- linear coupling between any two directions of the vehicular planar motion and computes the sequence of the optimal motion states for following the desired path. Third, a hierarchical control structure is proposed to separate the motion controller into a NMPC based path planner and a terminal sliding mode control （TSMC） based path fol- lower. As revealed through off-line simulations, the hier- archical methodology brings nearly 1700% improvement in computational efficiency without loss of control per- formance. Finally, the control algorithm is verified through a hardware in-the-loop simulation system. Double-lane- change （DLC） test results show that by using the optimalpredictive controller, the root-mean-square （RMS） values of the lateral deviations and the orientation errors can be reduced by 41% and 30%, respectively, comparing to those by the optimal preview acceleration （OPA） driver model with the non-preview speed-tracking method. Additionally, the average vehicle speed is increased by 0.26 km/h with the peak sideslip angle suppressed to 1.9~. This research proposes a novel motion controller, which provides the full dri

关键词： Vehicle dynamics Spatial transformationModel predictive control Sliding mode control Automated lane guidance

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Stability of Fullerene Cages:C_(30) to C_(70) and Their Dependence on Shared Pentagon Bonds

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1051-1056页

作者： WU Hai-Shun TIAN Xin-Xin jian jian-Feng FENG rui-Juan Chemistry and Material Science Institute Shanxi Normal University Linfen 041004 China

The topological characters of all fullerene isomers from C30 to C70 with respect to their number of shared pentagon bonds have been investigated. Systematic calculations were also carried out at the B3LYP/6-31G^＊ level. It is found that the most stable structure has the smallest number of shared pentagon bonds, and the relative energies of a given size show an increasing tendency to rise with Nss number which denotes the number of C-C bonds shared by pentagon. The topological criterion that has extremely low computational cost can be used as filtering principle to prescreen the thermodynamically viable fullerenes and predict the relative stability of isomers.

关键词： fullerene density functional theory most stable isomer topology Nss

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The reaction mechanism and interfacial crystallization of Al nanoparticle-embedded Ni under shock loading

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Defence Technology（防务技术） 2024年第3期33卷 114-124页

作者： Yifan Xie jian-Li Shao rui Liu Pengwan Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Explosion Protection and Emergency Disposal Technology Engineering Research Center of the Ministry of Education Beijing100039China

The shock-induced reaction mechanism and characteristics of Ni/Al system,considering an Al nanoparticle-embedded Ni single crystal,are investigated through molecular dynamics *** the shock melting of Al nanoparticle,interfacial crystallization and dissolution are the main *** reaction degree of Al particle first increases linearly and then logarithmically with time driven by rapid mechanical mixing and following *** reaction rate increases with the decrease of particle diameter,however,the reaction is seriously hindered by interfacial crystallization when the diameter is lower than 9 nm in our ***,we found a negative exponential growth in the fraction of crystallized Al atoms,and the crystallinity of B2-NiAl(up to 20%)is positively correlated with the specific surface area of Al *** can be attributed to the formation mechanism of B2-NiAl by structural evolution of finite mixing layer near the collapsed *** shock melting of both Al particle and Ni matrix,the liquid-liquid phase inter-diffusion is the main reaction mechanism that can be enhanced by the formation of internal *** addition,the enhanced diffusion is manifested in the logarithmic growth law of mean square displacement,which results in an almost constant reaction rate similar to the mechanical mixing process.

关键词： Shock-induced reaction Molecular dynamics simulations Interfacial crystallization Reaction mechanism

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分子印迹膜-固相萃取-高效液相色谱法同时检测橙子中噻苯隆和氯吡脲

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食品科学 2025年第1期46卷 176-183页

作者：石雨王建豆瑞祁迎春董晓牛志睿任景俞黄华赵怡雪延安大学石油工程与环境工程学院延安市环境检测与修复重点实验室陕西延安716000 北京理工大学化学与化工学院北京100081

以聚多巴胺(polydopamine,PDA)修饰的聚偏氟乙烯(polyvinylidene fluoride,PVDF)膜为基膜,噻苯隆(thidiazuron,TDZ)为模板,甲基丙烯酸(methacrylic acid,MAA)为功能单体,乙二醇二甲基丙烯酸酯(ethylene glycol dimethacrylate,EGDMA)为交联剂,合成TDZ分子印迹膜(molecularly imprinted membrane,MIM),并将其应用于橙子中TDZ及其结构类似物氯吡脲(forchlorfenuron,CPPU)的高选择性同时提取。扫描电子显微镜表征结果表明,致密分子印迹聚合物通过PDA涂层固定在PDA@PVDF膜的三维网络结构表面;性能测试结果表明,MIM对TDZ和CPPU的吸附容量分别是相应非印迹膜的1.80、1.89倍,分别在20、30 min达到吸附平衡;MIM对干扰物质香豆素和3-叔丁基苯酚的特异性因子分别达到23.2和19.3。以MIM为固相萃取膜片,成功从橙子样品中高选择性同时提取TDZ和CPPU,在加标浓度为2.0、3.0、5.0μmol/L时,高效液相色谱法检测的加标回收率分别为90.3%~99.4%和88.2%~98.1%,相对标准偏差分别为0.9%~2.5%和1.2%~3.0%(n=3)。该方法能同时快速检测TDZ和CPPU,操作简单,具有较好的灵敏度、精密度及回收率,检测成本低,适用于果蔬中TDZ和CPPU残留的检测。

关键词：分子印迹膜固相萃取高效液相色谱法特异性识别噻苯隆氯吡脲

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Comparative experiment on treating digested piggery wastewater with a biofilm MBR and conventional MBR： simultaneous removal of nitrogen and antibiotics

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Frontiers of Environmental Science & Engineering 2017年第2期11卷 123-131页

作者： Xiaoyan song rui Liu Lujun Chen Tomoki Kawagishi Zhejiang Provincial Key Laboratory of Water Science and Technology Department of Environment in Yangtze Delta Region Institute of Tsinghua University-Zhejiang Jiaxing 314006 China School of Environment Tsinghua University Beijing 100084 China Aqua Development Center Mitsubishi Rayon Co. Ltd. Toyohashi 4408601 Japan

A biofilm membrane bioreactor （BF-MBR） and a conventional membrane bioreactor （MBR） were parallelly operated for treating digested piggery wastewater. The removal performance of COD, TN, NH4＋-N, TP as well as antibiotics were simultaneously studied when the hydraulic retention time （HRT） was gradually shortened from 9 d to 1 d and when the ratio ofinfluent COD to TN was changed. The results showed that the effluent quality in both reactors was poor and unstable at an influent COD/ TN ratio of 1.0±0.2. The effluent quality was signifcantly improved as the influent COD/TN ratio was increased to 2.3±0.5. The averaged removal rates of COD, NH4＋-N, TN and TP were 92.1%, 97.1%, 35.6% and 54.2%, respectively, in the BF-MBR, significantly higher than the corresponding values of 91.7%, 90.9%, 17.4% and 31.9% in the MBR. Analysis of 11 typical veterinary antibiotics （from the tetracycline, sulfonamide, quinolone, and macrolide families） revealed that the BF-MBR removed more antibiotics than the MBR. Although the antibiotics removal decreased with a shortened HRT, high antibiotics removals of 86.8%, 80.2% and 45.3% were observed in the BF-MBR at HRT of 5~4 d, 3-2 d and 1 d, respectively, while the corresponding values were only 83.8%, 57.0% and 25.5% in the MBR. Moreover, the BF-MBR showed a 15% higher retention rate of antibiotics and consumed 40% less alkalinity than the MBR. Results above suggest that the BF-MBR was more suitable for digested piggery wastewater treatment.

关键词： AlkalinityAntibioticsBiofilmDigested piggery wastewater (DPW)Membrane bioreactor

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组蛋白脱乙酰酶1基因抑制人脐静脉内皮细胞焦亡并减轻动脉粥样硬化及炎性反应

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中国组织工程研究 2025年第25期29卷 5351-5361页

作者：张国安石践宋宝国黄晓燕陕西省人民医院心血管外科陕西省西安市710068 陕西省人民医院陕西省感染与免疫重点实验室陕西省西安市710068

背景:细胞焦亡作为炎症细胞死亡的一种独特形式,在动脉粥样硬化病变的不稳定性中发挥重要作用。目的:探究重组B细胞淋巴瘤2相关蛋白A1(B-cell lymphoma 2-related protein A1,BCL2A1)在动脉粥样硬化中的作用机制。方法:①使用200μg/mL... 详细信息

背景:细胞焦亡作为炎症细胞死亡的一种独特形式,在动脉粥样硬化病变的不稳定性中发挥重要作用。目的:探究重组B细胞淋巴瘤2相关蛋白A1(B-cell lymphoma 2-related protein A1,BCL2A1)在动脉粥样硬化中的作用机制。方法:①使用200μg/mL氧化低密度脂蛋白处理人脐静脉内皮细胞24 h以诱导内皮损伤。随后,分别使用50 nmol/L BCL2A1干扰质粒(sh-BCL2A1)和1.5μg/mL组蛋白脱乙酰酶1基因(histone deacetylase 1 gene,HDAC1)过表达载体(pcDNA-HDAC1)转染人脐静脉内皮细胞,或同时转染pcDNA-HDAC1和BCL2A1过表达载体(pcDNA-BCL2A1)。转染后培养48 h检测BCL2A1和HDAC1的表达水平、细胞活力、细胞焦亡水平以及BCL2A1乙酰化水平。②通过高脂喂养APOE-/-小鼠构建动脉粥样硬化小鼠模型进行体内验证。将500μL BCL2A1和HDAC1慢病毒过表达载体分别或同时尾静脉注射到小鼠体内,检测BCL2A1和HDAC1的表达水平以及小鼠动脉组织损伤情况。结果与结论:氧化低密度脂蛋白诱导的人脐静脉内皮细胞中BCL2A1上调,干扰BCL2A1可改善细胞活力并抑制细胞焦亡和炎症反应。此外,氧化低密度脂蛋白诱导的人脐静脉内皮细胞中HDAC1下调,通过促进BCL2A1去乙酰化提高了细胞活力及抑制了细胞焦亡和炎症反应。体内实验表明,BCL2A1在高脂喂养的小鼠动脉组织中高表达,而HDAC1低表达。此外,HDAC1通过促进BCL2A1去乙酰化减轻了高脂喂养诱导的ApoE-/-小鼠动脉组织病变。结果表明,HDAC1可能通过BCL2A1去乙酰化来抑制人脐静脉内皮细胞焦亡进而减轻动脉粥样硬化和炎症反应。

关键词：动脉粥样硬化 BCL2A1 HDAC1 乙酰化细胞焦亡

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HMFI分子筛Bronsted酸性位点与碱性分子的作用机制

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原子与分子物理学报 2025年第4期42卷 1-7页

作者：郑健秦康秦玉才宋丽娟中石化石油化工科学研究院有限公司北京100083 辽宁石油化工大学辽宁省石油化工催化科学与技术重点实验室抚顺113001

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_... 详细信息

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_(3)分子与HMFI分子筛的作用机制.研究表明分子筛Bronsted酸(简称B酸)强度与B酸数量没有强相关性,在考虑B酸位数量的同时须考虑B酸位的分布.酸性位点数量和分布的差异均可以调控NH_(3)分子的吸附构象,并且可以通过调节HMFI分子筛孔道对分子施加相互作用的模式,解析分子的结构和电子性质,精准调控分子的进一步转化.此项工作可以为未来高效多孔材料有效物种活性位的构建提供新思路.

关键词：密度泛函理论 HMFI分子筛 Bronsted酸性质吸附性能

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Effect of ramipril on progression of nonculprit lesions in patients with ST-elevation myocardial infarction after primary percutaneous coronary intervention

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Journal of Geriatric Cardiology 2019年第9期16卷 695-700页

作者： jian WANG song-Yuan HE Department of Cardiology Aerospace Central Hospital Aerospace Clinical Medical College of Peking University

Objective To investigate the effect of ramipril on progression of nonculprit lesions in patients with ST-elevation myocardial infarction(STEMI) after primary percutaneous coronary intervention(PPCI). Methods A total of 200 patients(60.1 ± 11.3 years) with STEMI who underwent successful PPCI from January 2010 to December 2013 were enrolled in this study. All patients underwent PPCI as treatment for culprit lesions. Patients were divided into two groups according to the dosage of ramipril used at hospital discharge as follows: high dosage group(2.5–10 mg, q.d.) and low dosage group(1.25–2.5 mg, q.d.). Clinical and angiographic follow-up was performed for 12 months. The primary endpoint was clinically-driven percutaneous coronary intervention(PCI) for nonculprit lesions. The clinical and angiographic features were analyzed. Results Clinical and angiographic follow-up was performed with 87 patients in the high dosage group and 113 patients in the low dosage group. The numbers of patients who underwent additional PCI were six and 20 in the high and low dosage groups, respectively. The rate of having additional PCI performed was lower in the high dosage group than in the low dosage group(6.90% vs. 17.70%, P = 0.03). Conclusions A high dosage of ramipril may prevent progression of nonculprit lesions, which could be the major cause of recurrent PCI in patients with STEMI after PPCI.

关键词： Nonculprit lesion Primary percutaneous coronary intervention Ramipril ST-elevation myocardial infarction

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A possible explanation for the electron/positron excess of ATIC/PAMELA

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Research in Astronomy and Astrophysics 2010年第1期10卷 39-46页

作者： rui-Zhi Yang Jin Chang jian Wu Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

Results from PAMELA and ATIC indicate that the Kaluza-Klein type dark matter particles could be the annihilation source of the observed excess of electrons and positrons. Assuming the existence of a nearby black hole with 10000-100000 solar masses and a point source boost algorithm, we apply the standard propagation model and find that the results fit the data well.

关键词： dark matter - black hole physics - cosmic rays

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Design,fabrication,and characterization of hierarchical mechanical metamaterials

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Frontiers of Mechanical Engineering 2024年第1期19卷 73-83页

作者： jian song Junfei YAN Bengang YI Automotive Engineering Research Institute BYD Auto Industry Co.Ltd.Shenzhen 518000China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China

Natural mechanical materials,such as bamboo and bone,often exhibit superior specific mechanical properties due to their hierarchical porous *** the principle of hierarchy as inspiration can facilitate the development of hierarchical mechanical metamaterials(HMMs)across multiple length scales via 3D *** this work,we propose self-similar HMMs that combine octet-truss(OCT)architecture as the first and second orders,with cubic architecture as the third or more *** HMMs were fabricated using stereolithography 3D printing,with the length sizes ranging from approximately 200µm to the centimeter *** compressive stress–strain behaviors of HMMs exhibit a zigzag characteristic,and the toughness and energy absorption can be significantly enhanced by the hierarchical *** compressive moduli are comparable to that of natural materials,and the strengths are superior to that of most polymer/metal foams,alumina hollow/carbon lattices,and other natural ***,the flexural stress–strain curves exhibit a nonlinear behavior,which can be attributed to the hierarchical architecture and local damage *** relatively high mechanical properties can be attributed to the synergistic effect of the stretch-dominated OCT architecture and the bending-dominated cube ***,an ultralight HMM-integrated unmanned aerial vehicle(HMM-UAV)was successfully designed and *** HMM-UAV is~85%lighter than its bulk counterpart,remarkably extending the flight duration time(~53%).This work not only provides an effective design strategy for HMMs but also further expands the application benchmark of HMMs.

关键词： 3D printing mechanical metamaterials hierarchical architecture mechanical behavior unmanned aerial vehicle(UAV)

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