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Linearized Transformed L1 Galerkin FEMs with Unconditional Convergence for Nonlinear Time Fractional Schr¨odinger Equations

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Numerical Mathematics(Theory,Methods and Applications) 2023年第2期16卷 348-369页

作者： Wanqiu Yuan Dongfang Li chengjian Zhang School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China

A linearized transformed L1 Galerkin finite element method(FEM)is presented for numerically solving the multi-dimensional time fractional Schr¨odinger equations.Unconditionally optimal error estimates of the fully-discrete scheme are proved.Such error estimates are obtained by combining a new discrete fractional Gr¨onwall inequality,the corresponding Sobolev embedding theorems and some inverse inequalities.While the previous unconditional convergence results are usually obtained by using the temporal-spatial error spitting approaches.Numerical examples are presented to confirm the theoretical results.

关键词： Optimal error estimates time fractional Schr¨odinger equations transformed L1 scheme discrete fractional Gr¨onwall inequality

Role Dynamic Allocation of Human-Robot Cooperation Based on Reinforcement Learning in an Installation of Curtain Wall

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工程与科学中的计算机建模(英文) 2024年第1期138卷 473-487页

作者： Zhiguang Liu Shilin wang Jian Zhao Jianhong Hao Fei Yu School of Control and Mechanical Engineering Tianjin Chengjian UniversityTianjin300384China Comprehensive Business Department CATARC(Tianjin)Automotive Engineering Research Institute Co.Ltd.300339China School of Mechanical Engineering Hebei University of TechnologyTianjin300130China

A real-time adaptive roles allocation method based on reinforcement learning is proposed to improve humanrobot cooperation performance for a curtain wall installation task.This method breaks the traditional idea that the robot is regarded as the follower or only adjusts the leader and the follower in cooperation.In this paper,a self-learning method is proposed which can dynamically adapt and continuously adjust the initiative weight of the robot according to the change of the task.Firstly,the physical human-robot cooperation model,including the role factor is built.Then,a reinforcement learningmodel that can adjust the role factor in real time is established,and a reward and actionmodel is designed.The role factor can be adjusted continuously according to the comprehensive performance of the human-robot interaction force and the robot’s Jerk during the repeated installation.Finally,the roles adjustment rule established above continuously improves the comprehensive performance.Experiments of the dynamic roles allocation and the effect of the performance weighting coefficient on the result have been verified.The results show that the proposed method can realize the role adaptation and achieve the dual optimization goal of reducing the sum of the cooperator force and the robot’s Jerk.

关键词： Human-robot cooperation roles allocation reinforcement learning

Fibrous Aerogels with Tunable Superwettability for High-Performance Solar-Driven Interfacial Evaporation

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Nano-Micro Letters 2023年第5期15卷 51-68页

作者： chengjian Xu Mengyue Gao Xiaoxiao Yu Junyan Zhang Yanhua Cheng Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620People’s Republic of China

Solar-driven interfacial evaporation is an emerging technology for water desalination.Generally,double-layered structure with separate surface wettability properties is usually employed for evaporator construction.However,creating materials with tunable properties is a great challenge because the wettability of existing materials is usually monotonous.Herein,we report vinyltrimethoxysilane as a single molecular unit to hybrid with bacterial cellulose(BC)fibrous network,which can be built into robust aerogel with entirely distinct wettability through controlling assembly pathways.Siloxane groups or carbon atoms are exposed on the surface of BC nanofibers,resulting in either superhydrophilic or superhydrophobic aerogels.With this special property,single component-modified aerogels could be integrated into a double-layered evaporator for water desalination.Under 1 sun,our evaporator achieves high water evaporation rates of 1.91 and 4.20 kg m^(-2)h^(-1)under laboratory and outdoor solar conditions,respectively.Moreover,this aerogel evaporator shows unprecedented lightweight,structural robustness,long-term stability under extreme conditions,and excellent salt-resistance,highlighting the advantages in synthesis of aerogel materials from the single molecular unit.

关键词： Cellulose aerogel Tunable wettability Thermal insulation Robust interface Solar vapor generation

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中药复方对猪繁殖与呼吸综合征的防治效果及母猪生产性能的影响

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畜牧与兽医 2024年第7期56卷 112-116页

作者：董续加汪志恒林芳竹黄志洪杨国虎张成健武志勇王德云海南罗牛山畜牧有限公司海南海口570100 南京农业大学江苏南京210095 湖北九灵草生物科技有限公司湖北咸宁437000

旨在研究中药复方对猪繁殖与呼吸综合征(PRRS)的防治效果以及对母猪生产性能、仔猪健康状况的影响。选择罗牛山某猪场6栋母猪区约4 500头PRRS发病母猪(长白×大约克)作为对照组,每吨饲料添加磷酸替米考星1 kg和复方阿莫西林0.5 kg,自试... 详细信息

旨在研究中药复方对猪繁殖与呼吸综合征(PRRS)的防治效果以及对母猪生产性能、仔猪健康状况的影响。选择罗牛山某猪场6栋母猪区约4 500头PRRS发病母猪(长白×大约克)作为对照组,每吨饲料添加磷酸替米考星1 kg和复方阿莫西林0.5 kg,自试验开始连续添加7 d;另在发病情况相似的7栋母猪区选择约4 500头同品种母猪作为试验组,拌料饲喂中药复方,每吨饲料添加1 kg九灵甘蓝素和1 kg九灵黄芪素,自试验开始连续添加15 d。检测发病母猪主要生产性能指标、PRRSV抗原、循环阈值(Ct值)及仔猪的出生重、断奶重等。结果:在使用抗生素和中药复方之后,发病母猪中流产数和窝均死胎数明显减少(P0.05),死淘率显著降低,母猪产仔数及窝均健仔数均显著增加(P<0.05),表明中药复方对PRRS的防控效果与抗生素类似;但试验组在8月的流产率、窝均死胎数显著低于对照组(P<0.05),脐带血、睾丸去势液和流产母猪样本抗原阳性率均显著低于对照组(P<0.05),表明中药复方降低了PRRS复发的风险。综上,添加中药复方可降低PRRSV抗原阳性率,减少PRRS的发病率,稳定病情,并能提高母猪的生产性能和仔猪抗病能力。

关键词：猪繁殖与呼吸综合征中药复方抗生素母猪生产性能

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Manganese-Catalyzed Anti-Markovnikov Hydroarylation of Enamides:Modular Synthesis of Arylethylamines

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Chinese Journal of Chemistry 2022年第13期40卷 1546-1552页

作者： Yjie He Chaoyu Du Jian Han Jie Han chengjian Zhu Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu 210023China Green Catalysis Center College of Chemistry and Molecular EngineeringZhengzhou UniversityZhengzhouHenan 45000iChina Advanced Catalytic Engineering Research Center of the Ministry of Education Hunan UniversityChangshaHunan 410082China

The arylethylamine framework is a prevalent motif in a great range of biologically important organic compounds.One intractable task for frontline drug discovery is to find structurally new medicine candidates instead of opioid,based on the construction of a rich chemical space of arylethylamine motif In this report,a practical protocol for the synthesis of arylethylamine functionality common in pharmaceutical chemicals has been developed.It proceeds by Mn-catalyzed anti-Markovnikov hydroarylation of electron-rich enamides under mild conditions without the use of ligands.In spite of mismatched electronic effects during the manganese-mediated migratory insertion process,both terminal and internal enamides can be regioselectively hydroarylated with various aryl boronic acids in 15 min.Also,the successful hydroalkenylation of enamides with alkenyl boronic acids in air atmosphere affords an elegant route to synthetically useful β-alkenylated amines in satisfactory yields.The synthetic robustness and practicality of the reaction reveal its simple operation,short reaction time,viability on a gram-scale and its value in late-stage modification of complex molecules.

关键词： Alkenes Anti-Markovnikov Homogeneous catalysis Amines Difunctionalization

Enhanced conductivity and stability of Co_(0.98)Cu_(x)Mn_(2.02−x)O_(4)ceramics with dual phases and twin structures

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Journal of Advanced Ceramics 2023年第9期12卷 1742-1757页

作者： chengjian Ma Longhua He Lei Bi Hong Gao Jianxiang Ding Analytical and Testing Center Yancheng Institute of TechnologyYancheng 224051China School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China School of Resource Environment and Safety Engineering University of South ChinaHengyang 421001China School of Mathematics and Physics Yancheng Institute of TechnologyYancheng 224051China School of Materials Science and Engineering Anhui University of TechnologyMa’anshan 243002China

Semiconductor materials with heterogeneous interfaces and twin structures generally demonstrate a higher concentration of carriers and better electrical stability.A variety of Cu-doped Co_(0.98)Cu_(x)Mn_(2.02−x)O_(4)(0≤x≤0.5)negative temperature coefficient(NTC)ceramics with dual phases and twin structures were successfully prepared in this study.Rietveld refinement indicates that the content of a cubic spinel phase increases with increasing Cu content.The addition of Cu can promote grain growth and densification.Atomic-level structural characterization reveals the evolution of twin morphology from large lamellae with internal fine lamellae(LIT lamellae)to large lamellae without internal fine lamellae(L lamellae)and the distribution of twin boundary defects.First-principles calculations reveal that the dual phases and twin structures have lower oxygen-vacancy formation energy than those in the case of the pure tetragonal and cubic spinel,thereby enhancing the transmission of carriers.Additionally,the three-dimensional charge-density difference shows that metal ions at the interface lose electrons and dwell in high valence states,thereby enhancing electrical stability of the NTC ceramics.Furthermore,the additional Cu ions engage in electron-exchange interactions with Mn and Co ions,thereby reducing resistivity.In comparison to previous Cu-containing systems,the Co_(0.98)Cu_(x)Mn_(2.02−x)O_(4)series exhibit superior stability(aging value≤2.84%),tunable room-temperature resistivity(ρ),and material constant(B)value(17.5Ω·cm≤ρ≤7325Ω·cm,2836 K≤B≤4315 K).These discoveries lay a foundation for designing and developing new NTC ceramics with ultra-high performance.

关键词： negative temperature coefficient(NTC)ceramics Cu-containing spinel high electrical stability twin structure first-principles calculation electron-exchange interaction

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龙羊峡水库蓄丰补枯特征研究

水文 2024年第3期44卷 47-51,81页

作者：席海潮解阳阳刘赛艳黄成剑张钦胡华清扬州大学水利科学与工程学院江苏扬州225009 扬州大学江苏省高效节能大型轴流泵站工程研究中心江苏扬州225009 扬州大学现代农村水利研究院江苏扬州225009 宁波水利水电规划设计研究院有限公司浙江杭州310000

丰、枯水期末蓄水量是影响多年调节水库蓄丰补枯规则的关键要素。以黄河上游龙羊峡水库为研究对象,基于该水库的历史运行资料,考虑水库丰、枯水期的来水量、初始蓄水量等影响,采用多元线性回归方程建立调度函数,推求丰、枯水期水库增补... 详细信息

丰、枯水期末蓄水量是影响多年调节水库蓄丰补枯规则的关键要素。以黄河上游龙羊峡水库为研究对象,基于该水库的历史运行资料,考虑水库丰、枯水期的来水量、初始蓄水量等影响,采用多元线性回归方程建立调度函数,推求丰、枯水期水库增补水量,确定水库的丰、枯水期末蓄水量。结果表明:(1)龙羊峡水库丰水期增水量的距平值与来水量的距平值呈显著的正相关性(R^(2)=0.42),枯水期水库补水量的距平值与初始蓄水量的距平值呈显著的正相关性(R^(2)=0.16);(2)由调度函数推求的丰水期增水量与实际增水量的相关性良好(R^(2)=0.62),枯水期补水量与实际补水量相关性也较好(R^(2)=0.38)。研究成果可为龙羊峡水库调度规则的建立提供依据,也可为其他多年调节水库的调度提供参考。

关键词：蓄丰补枯多元线性回归相关分析多年调节龙羊峡水库

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复杂地质条件土层参数对暗挖的影响与地表沉降监测

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粘接 2024年第4期51卷 161-164页

作者：祝李京覃亚伟江承建武汉华中科大检测科技有限公司湖北武汉430074 中建三局基础设施建设投资有限公司湖北武汉430061

针对地铁暗挖区间地表沉降的监测难度较大问题,基于卵石、泥岩复杂地质的土层参数影响开展有效分析,提出卵石、泥岩地质条件下地铁暗挖区间地表沉降监测研究方法。构建了地铁暗挖区间有限元分析模型,设定土体参数值,将参数代入有限元分... 详细信息

针对地铁暗挖区间地表沉降的监测难度较大问题,基于卵石、泥岩复杂地质的土层参数影响开展有效分析,提出卵石、泥岩地质条件下地铁暗挖区间地表沉降监测研究方法。构建了地铁暗挖区间有限元分析模型,设定土体参数值,将参数代入有限元分析模型,得到土体参数弹性模量、内摩擦角和粘聚力对地表沉降影响;按照当前工程概况设定相应的监测方案,监测地表沉降。由监测结果可知,地铁暗挖区间掘进后会使地表沉降出现明显的滞后规律,导致地铁暗挖区间的累计沉降值大,存在危害性。

关键词：卵石、泥岩地质地铁暗挖区间地表沉降监测离散性

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剥离黏液层改性污泥回用对污泥颗粒化过程的影响

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工业水处理 2024年第4期44卷 76-83页

作者：上官一将文正红贾燕茹杨成建李志华西安建筑科技大学环境与市政工程学院陕西西安710055 西安市环境工程装备智能化技术重点实验室陕西西安710055 西安建筑科技大学西北水资源与环境生态教育部重点实验室陕西西安710055

胞外聚合物(Extracellular polymeric substances,EPS)的资源化回收已经得到了广泛研究,但关于剥离EPS后污泥就地回用至污水生物处理系统的研究甚少。通过对剥离黏液层改性后的污泥进行考察发现,改性后的污泥仍具有良好的微生物活性,具... 详细信息

胞外聚合物(Extracellular polymeric substances,EPS)的资源化回收已经得到了广泛研究,但关于剥离EPS后污泥就地回用至污水生物处理系统的研究甚少。通过对剥离黏液层改性后的污泥进行考察发现,改性后的污泥仍具有良好的微生物活性,具备较好的底物降解能力;且相较于原泥,改性污泥的胞外蛋白质与胞外多糖质量比[m(PN)/m(PS)]由1.37提升至1.84,Zeta电位绝对值降低了25.97%,絮凝性能提升,因此改性污泥可回用于污水生物处理系统,并改善其性能。进一步地,研究了改性污泥连续回用至DE型氧化沟系统对其性能及污泥性质的影响,结果表明,随着回用天数的增加,污泥的m(PN)/m(PS)升高,系统内污泥开始颗粒化,粒径大于200μm的颗粒污泥占比达到了30%以上,污泥颗粒化持续增强。因此,连续回用剥离黏液层改性污泥至DE型氧化沟系统,可以促使系统内污泥颗粒化,从而为连续流氧化沟系统的污泥颗粒化提供了新方法。

关键词：黏液层改性污泥回用颗粒污泥 DE型氧化沟

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